Flight or Fight?

Introduction

It is always of interest to hobbyist to understand the behaviour of the organisms we raise, to best take care of them.

Fish behaviour though, is definitely extremely complex, something that cannot simply be categorized or idealized. Behavioural ecologists have spent countless years understanding the complex relationships between various factors that make up an organism, and how that dictates how it deals with the surroundings.

As we all know, some fish displays aggressive behaviour towards any of its conspecifics. Others, only to the same sexes. Then there are those that besides a 'mate', will definitely take on anything else.

There are fish that will not tolerate any coinhabitants, and those that will easily. There are those 'in-between' as well. Sometimes, it seems like it all just varies with each specific individual.

Whilst certainly the combination of behavioural factors is part of what makes each and every species unique, and then every individual amongst that species, there are certain behaviours that we can observe as being consistent throughout many species. By understanding these behaviours firstly, and relationships between these behaviours secondly, we can definitely have a more profound understanding of our live stock.

Fight or Flight

The 'fight or flight' response is one that is deeply ingrained in many animals, one that trascends the various animal kingdoms.

'Fight or flight' denotes a very simple biological decision, that of whether to run from a dangerous situation, or deal with it head on. Whilst this is generally most obvious in fish, you would probably have stumbled upon it elsewhere.

Did you ever notice that many clams would close up quickly if you shadow the lights? It is a response to danger, or at least 'perceived' danger. In the wild, they associate being shadowed with the presence of something above, shading the Sun. This something 'above' could very well be a predator, hence the closing up 'flight' response.

'Fight' and 'Flight'?

As we can see above, the definition of 'fight' and 'flight' can be quite broad. 'Flight' doesn't mean that one has to definitely run away. It could be something like the clam's 'closing up', or a coral retracting its tentacles into itself. Neither of this allows the organism to go anywhere far, but it is enough to escape from a predator.

'Fight' too, does not necessarily mean 'fight' in the sense of a battle ensuing. A 'fight' response can simply involve the act of rasing one's defenses, such as a pufferfish puffing up, or a lionfish raising its spines. Essentially, if 'flight' is an act of escape, 'fight' is an act of defiance.

It is important to understand the definition of these words, to fully understand why our livestock do what they do. Or at least, provide some explanation for it.

A Perceived Threat

One of the factors that we have to keep in mind is that a 'threat' may be perceived, i.e. non-existent.

However, due to the way organisms are programmed, they may still react nonetheless - for example, with the clams and shadowing example above.

Why is this important? We must remember then that what we know or perceive is not as important as what our live stock know or perceive.

One of the most obvious example of this is with cichlids. Many cichlids fall prey to birds and the likes. Birds rely mainly on sight to spot their prey, and in areas of open water, they can obviously spot their prey better.

Cichlids, therefore, avoid open areas like the plague, unless there is indication otherwise. Over time, they will eventually 'brave the outdoors', though it will take time for them to do so. Even then, their fight or flight response kicks in, if there is any semblance of danger, such as when you approach. Though in this case, it will almost always be a 'flight' response. This is because everything boils down to survival (and passing down of their genes), and in situations where they have little chance to fight back, their instinctive response is to run away.

So what can you do? You can turn off their 'fight or flight' response by adding what are called dithers, or in other words fish that acts as a safety indication. There are many open water fish that will brave the open in large numbers, such as rainbowfish. With these in the aquarium, it will give the cichlid a sense of safety. If these fish are not being eaten, then a likelihood of predators is low.

A True Threat

Understanding the 'fight or flight' response is also important to understand many of the interactions between our livestock.

When dealing with predators or major dangers, the instinct is to run away. When dealing with a much more managable danger, such as competition, then the instinct gears more towards te 'fight' response. Fight for mates, fight for food, fight for territory.

Many of this will still depend on the situation, but others will be almost exclusively a 'fight' response, when the 'flight' response is unavailable.

How is this important, and what does this explain? This explains a lot. Have you ever seen a cichlid defend its young? For many cichlids, the young are defenseless and are totally reliant on the parents. In such cases, leaving the young means certain death, and so even if possible, cichlid parents may not leave their youngs, in order to protect them. When the 'flight' response is forced to be switched off, the 'fight' response tends to be much more intense as well.

This is why many fish are so much more aggressive during and after breeding.

This is the same for territorial aggression. Having chosen a home, they have nowhere else to flee to, and so will do anything to protect it. Well in the wild, they can abandon their home, but...

In Our Aquarium

Our aquarium is quite special because we put fish together into a box that is probably at least a thousand times smaller than their natural habitat. At least. At least.

So don't be surprised if there is a lot of territorial encroachment, or if there is a lot of 'fight' responses going on. It is easy for a fish to be cornered, and obviously when cornered - the 'flight' choice is gone. And so, fight.

One major is issue is... what happens if both 'fight' and 'flight' are unavailable options? Have you ever seen your fish tucked away in the corner of your aquarium, afraid of coming out? Yeah...

So how do we control this.

Simple. We just have to make it so that the fish don't need to choose between 'fight' or 'flight'.

Okay, it is not as simple as that.

Think back to the example above. Most cases result from a fish addition into a tank with a fish that already has a territory. The fish feels like it needs to protect it, and will chase away the invader (the new fish). On the other hand, in nature, the invader might just run away, but in our aquariums, they will still be somewhere around. Having not manage to chase away the invader, the defender just have to try, and try, and try again. Even when the 'invader' is tucked in the corner. So next time, don't blame that 'aggressive' fish of yours. It is just protecting its territory, and is probably just as scared.

There are many methods that can work, but usually 'resetting' the aquascape will help. When this happens, no one has territories, and so everyone has to establish something. In this case, it might just work out as fish do not actually require that big of a territory. The issue normally is that once established, a territory keeps on getting bigger and bigger, until it meets the edge of another where it stops. So multiple territories established at once will work, but sequential additions mean that something will encroach upon something else's territory, and whilst fish are happy to have a limited territory from the beginning, they do not like a big territory being narrowed down.

The above is just one issue that arises from the 'fight or flight' response. There are many others, such as issues with fish running into rocks and the likes and hurting themselves out of fright. All of this must be managed, by reducing the need for the fish to resort to the 'fight or flight' reaponse.

Because when they need to initiate that response, they feel endangered, and will be stressed out and may exhibit dangerous behaviour. We definitely don't want that.

Conclusion

This really is just a short article on this behaviour. It is truly much more complex than this, but you should get the general idea. The thing is you must always keep this in mind as a consideration, when determing why your live stock is behaving in a certain way. 'Why is my fish spazzing out? Why is my corals retracting? Why is my anemone running amok? Why is my clam moving? Why are my goby and blenny not getting along?' Well. 'Are they running away or dealing with it head on? Are they initiating a 'fight or flight' response? How can I alleviate this?'

8 Marine Hobby Myths That Just Aren't True!

Introduction

Whether one is new to the hobby or has been around for a long time, there will always be stories out there. Some are fully valid and proven time and time again. Others, despite its incomplete truth, seems to somehow persitently remain and proliferate, keeping itself alive through the ages. The retention of these myths rely on its attachment to truths. Unfortunately the attachment makes it absolute in many's minds, and when the time comes that these myths prove wrong, no action is taken. This leads to just endless problems for us, the hobbyists, and the lives that we care for. For the good of all our fish and corals and more, it is time we separate them once and for all.

1. Corals only need light to grow

One of the biggest, and most persistent myth surrounding corals is the requirements for growth. Many will tell you that corals only need light to grow, much like plants.

Well firstly, plants need more than just light to grow. As plants grow, more cells and biological products are created. And unlike in Harry Potter, matter don't just come out of nowhere. So in a closed system like an aquarium, where does all that matter the corals need come from? Well, not from the lights, that's for sure. I'm pretty sure that if you stand in the light, matter don't suddenly appear on your skin. :)

2. Nitrates and phosphates are inherently bad for corals

Yes and no. Context! Context is important. Firstly, no chemical is inherently good or bad. It depends on whether it can be used or if it causes harm, and for/by what.

Do you remember what lives within corals, turning 'light' into usable energy? Zooxanthellae (Symbiodinium). And they are, guess what, symbiotic algae. Yes, algae. To be precise, they are dinoflagellates.

Remember all that algae in your aquarium? Remember why people say 'nitrates and phosphates' are bad? Because algae consumes it. Waitttt, what did we say zooxanthellae was again? Oh right, algae.

Yep, your corals actually do need phosphates and nitrates (and other nutrients) to grow. Surprise, surprise.

3. Nothing measured is nothing existing

Measured 0 for your PANN (phosphates, ammonia, nitrites and nitrates)? Yet seeing algae all over? Well simple. No PANN measured doesn't mean no PANN existing. Reefs are like forests, in that nutrients added can be uptaken very quickly. So even if you overfeed, by the tine you measured for PANN it may have all been consumed by algae and the likes. This is especially true when you already have plenty of algae growing, which is the state most reach before realizing 'oh crap so much algae, better reduce feeding'.

It truly is hard to gauge how much is overfeeding and how much is 'just right'.

Sometimes, it is best to not rely on tests, and rather on the visual signs within your aquarium.

4. Stocking many fish/corals at once is instant death

This is a big myth out there, and it stems from many reasons, none of which is exclusive and justifies this myth.

The biggest reason for the continuance of this myth is that stocking needs to be slow, for your biological filtration system (microbes) to adapt to the increase in bioload. But as I detailed in this blog post here, if your biogical filtration system needs to adapt after each addition (especially the first), you are doing it wrong.

A proper cycle should prepare your aquarium for whatever first addition(s) you make. And once your aquarium is ready, no matter if it is one fish or ten fish (assuming all other factors allow), you will be able to add them all in.

There are many other reasons that people use, such as:

-The longer the aquarium has existed, the more stable it is.

-Compatibility is important.

-Enough territories are required.

-The keeper will be more experienced as time goes on.

And so on.

As can be clearly seen, most of the reasons are exclusive from what they actually purports to support, pertaining more to 'tank readiness' than anything. Like I said above, if your aquarium is ready, then your aquarium is ready.

Think about it. If you have enough territories, then whether you add fish one at a time or multiple at once, that won't change territories.

Same with compatibility. If they are compatible, then regardless, they will be compatible. Adding fish slowly won't somehow make them 'more compatible'. On the contrary, many fish species are highly territorial, and when added together has a better chance of settling territories right off the bat. Adding one by one means that there is a much higher chance that the first additions have taken big territories, leaving newer additions with nothing.

5. A cycle finishes when you see a reduction in AN (ammonia and nitrite) to zero

Oh and nitrate too, sometimes. This is not true, and deserves its own special mention. The cycle, which should be better called the 'bacterial propagation phase' (BPP), only properly completes when you have a healthy population of bacteria.

Think about this way. You can have an aquarium with nothing except saltwater, and you'd measure nothing. Does that mean it is cycled? Hm... (no, it is not).

6. LEDs/T5/MH/etc. is better/worse

The simple truth is be it LEDs, T5s or MHs (and a number of other types of lighting), they can all work, and work well. That doesn't mean that you can just plop any light on a tank and your corals would bloom though.

Remember, it all depends on the actual spectrums, efficiency, and more. If your lighting system (regardless of what type it is) produces the correct lighting for coral growth, then the simple truth is, your corals will grow.

7. Dead rock always leaches phosphates

The theory behind this is that if we leave live rock out, organisms deep in the rock will die and decompose. This will leach out into the aquarium slowly, and basically forever. And because the organisms die so far within, nothing can take advantage of the organics in there.

The truth is very different. We truly underestimate the capabilities if bacteria and other microbes to colonize every surface possible.

If you 're-cycle' the rock properly, all that organics will be (relatively) quickly consumed.

8. You need at least xyz watts of lighting per litre/gallon/whatever

The idea that somehow, growth of corals always require a certain wattage over a certain volume.

This is one of the oddest myths out there, as there are just so many things wrong with it. Firstly, Even if you have a certain amount of wattage over your tank, and it is not in the correct color spectrum, then good luck. See if your corals love all-UV light. :)

Additionally, a single volume can mean many different types of aquariums. A tank that is 3ft long, wide and high has the same volume as one that is 6ft long, 3ft wide and 1.5ft high. But you'd need to consider your lighting very carefully with the 3ft high, as you need the light to be able to punch to the bottom of the tank. Compared to 1.5ft, which is much easily reached.

Additionally, sometimes two tanks of the same width and length, but different heights can use the exact same light as the light would have the ability to cover either heights. So to illuminate one that is say, 1ft high, and one that is 2ft high, there may not need to be an increase in wattage or anything of the likes.

Conclusion

The amount of myths out there is humongous, and these just represent a small proportion. They are though, very commonly dispersed around the community. Next time you see one of them around, think of this post. :)

Any questions, please ask!

Live Rock? Base Rock? Dead Rock? Cured Rock? Where to even START?

Introduction

Rocks serves many purposes in an aquarium. From being a part of the decoration, to breaking up waves and acting as a surface to place corals. More importantly, it is a biological filter media, capable of filtering our aquariums effectively.

Yet, it can be very confusing when purchasing rocks for our aquariums. What type to buy? What are the advantages and disadvantage of each type of rock?

This article will explore the broad type of rocks available, and just what it means for the rock to be labeled as such.

Live Rock

Live rock at an aquarium store. Most stores will store their live rock in such large vats of water, until the time is right for a hobbyist to pick up theirs. This here is a picture taken at Majestic Aquariums.

Live rock is in simplest terms, rock taken from a marine system/environment. In theory, live rock would contain much of the life originally found in and on the rocks, as it was in the ocean or from another aquarium. In reality, the trip from the ocean (or another aquarium) to the aquarium store (or to your aquarium) would have seen some of the organisms dying off. This is exactly what is normally referred to as 'die-off' when people discuss rocks.

Due to that, the straight addition of live rock to an existing aquarium must be carefully considered, as the die-off can foul up the water quickly. Of course, it would depend on just how much die-off there is, the amount of rock you are adding in, your aquarium volume and your aquarium filtration capabilities. Essentially this: if your aquarium can, at all points in time post-addition, handle the concentration of waste from the rock, then you are safe.

Cured Rock

Cured rock is rock that does not produce 'waste products' as live rock do, being safe to add straight into an existing aquarium.However, this means that 'cured' rock can either be live rock or dead/base rock, and therefore can cause confusion.

Cured rock may go through a full curing process, whereby die-off is washed away or re-used by organisms on or in the rock. As much of the die-off can be washed away, the amount of beneficial bacteria (and organisms) existing in and on the rock can be aplenty, or minimal. Many curing processes result in cured rock left for too long, or not done properly, and almost everything has died and completely decomposed (before being drained away). Although these rocks would not produce waste - it is because there's practically nothing left to produce waste, not because it is thriving with bacteria that breaks down waste.

Therefore, take into careful consideration what you are attempting to do when purchasing cured rock, and what way the rock has been cured. It is best to double-check before purchasing, what type of cured rock you are getting.

Dead/Base Rock

CaribSea 'life=like' base rock. This type of base rock is designed to look like rock with coralline algae coverage. CaribSea distributes plenty of types of rocks.

Dead or base rock are generally the ones you see that look just like any other rock existing out there. There really isn't much life on it.

Depending on how the rock is stored, it could be completely sterile/clean or full of dirt/detritus/dead organisms. The first is no different from cured rock (and so basically some cured rock are dead/base rock, as mentioned above). The latter when added to an aquarium can result in a situation no different than that seen with live rock, with plenty of unwanted molecules and chemicals released into the water. In fact, if it was stored in areas exposed to 'unnatural' chemicals, it is best to give the rock a good rinse/clean first.

Conclusion

There really are just three types of rocks out there, and can even be divided into two categories - either live rock ('containing life') or base/dead rock ('no life'). Either can be cured, or uncured.

Note that even though rocks can offer extreme filtration capacities, it will still depend on the origin of the rock itself. Rocks from certain reefs are more porous than others, and hence offer better filtration capabilities. It is therefore worth it, not to just know the state of rock you are purchasing, but also the particular type of rock it is.

Happy hunting!

The Ons and Offs of Cycling

Introduction

Following on from the previous from the previous blog post, I do want to touch a bit on what type of equipment should be turned on or off during the cycle, and the reasons why. After all, this is a frequent query that people have.

To be frank, if we consider the purpose of a cycle, then the answer is quite straight forward. And that, will also be my approach to answering this.

Let's consider now, why we cycle. The purpose is to grow a healthy population of bacteria, that can meet our filtration demands. Towards that, whether or not to use a piece of equipment are not is very simple.

I will divide the possible equipment set up in terms of the cycling process, and the post-cycling process.

During the Cycle

During the cycle, we want to focus on growing bacteria. There are two factors we want to especially consider here:

1.) We want to retain bacteria in the aquarium.
2.) We want to maintain enough food for the bacteria.

And so, let's cycle through the equipment list (pun intended).

Heater/Chiller

Yes - Contrary to popular belief, a heater (or chiller, but usually just the heater) turned on during the cycle is good. What temperature though? If you have live rock in with organisms besides microbes, then set it to around 27 degrees celcius (80 degrees fahrenheit for you Americans). If you've started off 'bare' then set it to 33 degrees (91 fahrenheit). Optimal growth rate for many nitrate-reducing bacteria is around 29 degrees, whilst others are more so at 37 degrees. It would be good to set your temperature to be somewhere around there, so that whilst it not quite optimal for any one species, you're getting good growth of all. Just make sure not to go above 37 degrees (98 fahrenheit), as some bacteria will stop liking it by then.

 Hydor Theo Heaters, a brand of heater suited for bigger tanks. Set it to higher temperatures and see your bacteria bloom!

Mechanical Filter Media

No - Don't worry about mechanical traps initially. You are not trying to remove anything. In fact, you definitely want any food particle to disperse as evenly as possible throughout your tank and sump. Remember, you want to grow bacteria, and it's not just about having food in the tank, it's about getting the food to your bacteria.

Poly-Filter, which also acts (mainly) as a chemical filter media. This is an extremely effective product capable of removing ammonia and so much more. Which also translates to DON'T.

Biological Filter Media

A MUST! - Where else do you think bacteria can grow? They need their own lovely home.

Marine Pure, one of many types of biological filter media. Live rock is actually also a type of biological filter media. Don't forget, you NEED a biological filter media of some kind. Bacteria need a home too.

Chemical Filter Media

No - Carbon, GFO and the likes are not recommended. Once again, think about what we are doing here. We actually WANT what we normally consider as 'waste products' to be in our aquariums, to feed bacteria. There's no point taking these out. Chemical filtration are useful in taking out certain toxic chemicals. But then the question is... why are those chemicals in there in the first place? If you need to, run these BEFORE the cycle. :) Then take it out once you begin.

 PhosBan, one of the many types of ferric chemical filter media out there. This product in particular is mainly used to remove phosphates... which is not quite what we want to remove. There are bacteria that sequesters phosphates after all. Basically any by-product of biotic processes is probably utilized by some species of bacteria.

Skimmer

NO JUST NO - Skimmers takes out practically EVERYTHING you want to retain, including bacteria and their sustenance. This will massively slow down your cycle. Just, no. Don't. Don't do it.

Need a compact skimmer? Tunze Comline is a good choice. Just remember, DON'T have it running until your tank is cycled.

Reactor

Maybe - It really depends on what type of reactor you are running, but most won't really aid in any way. Biopellet reactors, in theory, are good, but otherwise it won't be contributing much. Certain reactors that run carbon or the likes are no different from chemical filtration (because they are chemical filtration). See above for my opinion on chemical filtration.

A Deltec Calcium Reactor. Now let's think hard about this. We are slowly dissolving calcium into the water. What for? Sure it probably won't harm the bacteria, but it's not like they need the amount of calcium corals do, eh?

Water Circulator

A MUST! - Be it pumps or water circulators or the new awesome Maxspect Gyre, you need something to circulate your water from the getgo. That's the best way to ensure distribution of bacteria (and food) to where they need to be.

This is an Eheim Compact 1000. Many smaller (nano) tanks can actually get away with just a return pump, such as this one, and not need a water circulator in the tank itself! Hurray for limiting 'artificial' products in the display. :)

Lighting

No - At this point light will grow algae, and not much else. Bacteria don't need light to grow.

 Wowwwww, the colors from this Illumagic ComboRay! Corals would look great underneath it... if only my tank doesn't take months to cycle... oh wait!

Honorable Mention

Don't do a water change. Coral supplements/food are not necessary. Do feed fish food, or better yet, just purchase some seafood mix from the grocery store and feed the tank. I personally would recommend pureeing it and distributing all over the tank.

Post-Cycle

You can now run equipments as you like. Lower the setting on your heater/chiller to something more suited to what animals prefer.

Conclusion

In the end, I might have missed something (if I did, please let me know), but in general, you just have to consider this - 'what will affect my ability to propagate bacteria?'.

So long as it helps, I'd recommend it. If it doesn't, then don't have it. In essence you can definitely cycle a tank with all equipments on, but it will just take a long, long, long time. For comparison, I cycled my 36L nano in 7 days, and by day 10 I fully stocked it with 5 fish and a lot of corals. Not a single issue occured, in relation to my biological filtration capability. In the end, all I had in my aquarium was Marine Pure and coral sand (biological filter media), heater (set to 25 degrees celcius, I did forget to set it higher) and the return pump running.

As always, be flexible though. There may be times that you NEED to do something I don't recommend. But in general, stick to it and you'll see that your aquarium will cycle much faster. :)

Have fun!

What is 'Cycling'?

Introduction

'Cycling', a term commonly used in the aquarium-keeping hobby.

But what does it truly mean?

Well, let's start with a simple question. What would you answer, if I was to ask you 'what does it mean for a tank to be cycled?'

If your answer is 'ammonia, nitrite and nitrate are at zero' or something similar, then well... that's not quite right. The answer will be clear as you read on.

Even if your answer is something quite different, it may be good to read on anyways.

Etymology

The word 'cycling' arose as a term quite a while back, stemming from the 'nitrogen cycle'. Because of this, the term itself has led to some confusion of what 'cycling' truly means.

Background

'The nitrogen cycle' is one of the many chemical cycles on Earth, and also one of those that involves organisms during the cycle.

Do define simply, the 'nitrogen cycle' details the transition of nitrogen from one form to another, including it's common gaseous form (N2) to other forms, such as NH3, NO2, NO3 and so on.

A simplified diagram of the nitrogen cycle, depicting the common 'waste' products we as aquarists are worried about. Image from Wikipedia.

By now, you may have noticed that some of the forms listed is what tends to be deemed as waste products in our aquarium (although many exist in ionic form instead).

Nitrogen, however, does not simply exist in its common gaseous form or as waste products. Nitrogen is incorporated into organisms as part of DNA, amino acids, proteins and many other components of the organism.

Therefore when you feed your live stock, you will be introducing nitrogen and many other elements into the tank as various types of molecules. Some of this will be incorporated into the body of your life stock, the rest will be excreted as waste products - some are what we call 'ammonia', 'nitrite' and 'nitrate'.

Now why the mention of ammonia, nitrite and nitrate specifically?

They are the part of the nitrogen cycle that we have the most interest in, when talking about 'cycling'. Now, like I said, the goal of 'cycling' is not to deplete them, though their depletion is one indication that our goal is met (confused yet?).

Why Cycle?

This is where all your questions will be answered.

Despite what the term itself would suggest, 'cycling' is not to reduce your ammonia, nitrite and nitrate (or at least your ammonia and nitrite) to zero.

The purpose of cycling, is to actually end up with enough microbes living in your aquarium, to break down harmful waste products into non-toxic molecules.

In our aquariums, as in nature, microbes is the most effective form of filtration possible. They don't just 'filter' out unwanted chemicals. They also break down all sorts of organics into much simpler molecules that doesn't foul up the water.

Microbes can reproduce very quickly (it is said that bacteria can double in population every 20 minutes, provided the conditions are right). In a quarter of a day, one bacteria can become 260 thousand. In half a day, over 68 billion.

 Binary fission, the method of reproduction of (most) prokaryotes. Such as bacteria. Image from Wikipedia.

Of course, that doesn't happen, as they tend to be nutrient-limited and competition kills plenty. Oh and of course, they also end up as food for other organisms.

But what this means, is that in theory there can be plenty of bacteria in our aquariums to break down waste, and very quickly!

Cycling establishes this population of bacteria, so that when we do add live stock, our aquariums can deal with the bioload. As opposed to having ammonia, nitrite and nitrate skyrocket and kill everything.

Cycling Properly

Despite all that, cycling properly is simple.

Step 1: You need to start with two things:

1.) Bacteria
2.) Biological filter media (to house the bacteria)

Without any bacteria to start the cycle, you'll get nowhere. If you happen to have a completely sterile tank and have no bacteria introduced, then you're not going to get any bacteria to break down any waste. Once you add in your live stock, they'll overload your tank. They will introduce their own bacteria, but not enough to break down the waste.

 Live rock, the most common form of biological filter media (as it can also be used in the display). Photograph taken at Majestic Aquariums.

This is also why the 'cleaner' your start is, the longer it'll take for your tank to cycle. That or you'll have to manually add bacteria, which is really not a problem.

You also need some sort of biological filter media, or essentially 'bacteria houses'. Otherwise, they have nowhere to grow. Bacteria will live and reproduce suspended in solution, but they do much better when attached to a surface (and forming a biofilm, in many instances).

Biological filter media can be anything really, from live rock to Matrix, from Marine Pure to coral skeletons, from sand to clam shells. They can live on ornaments too, by the way.

So what's next?

Step 2: Propagate your bacteria!

With bacteria existing in your system, you need to now grow them, of course. How is it done?

Simple.

What do humans need to live and thrive and grow and reproduce?

 The human 'nutritional pyramid'. Obviously all this must come from different sources. The nutritional pyramid for bacteria will be different, but it's the same idea.

Well firstly, we need energy. Energy for us to do things. For bacteria, it's the same. Lucky for us, many bacteria utilizes what we regard as waste as sources of energy. And that's where we see ammonia being broken down to nitrite, then nitrate, then nitrogen gas.

Of course, just like us, energy is not enough. We can sustain ourselves, but what about reproduction? Where does all that material come from? How do we grow if we don't take in building blocks? It won't magically appear. It must come from somewhere.

That's why you also need to feed the bacteria, to let it bloom.

Think of it in terms of ourselves. We need carbohydrates for energy production, but we also need vitamins, minerals, protein, fibre, and more to actually build up our bodies and reproduce.

Step 3: Confirmation of cycle. :)

So you've let your bacteria reproduce and propagate. Great! Or, have you?

This is where the water parameter measures come in. A rise in ammonia, then nitrite, then nitrate (and the fall of the prior) would indicate that it is 'cycling', as ammonia-reducing bacteria is growing, then nitrite-reducing bacteria, then nitrate-reducing bacteria. When you first add some sort of food to your aquarium, that will produce plenty of ammonia. As ammonia is consumed and turned into nitrite, the level of ammonia decreases, whilst nitrite increases. And so on.

Now, having an efficient biological filtration system means that the bacteria should not just reduce ammonia to nitrogen gas, but reduce enough, quickly. I.e. effectively, and efficiently. There is no point if you have waste in there, and it remains there for too long. Likewise, there's no point in your biological filtration system not being able to handle the feeding regime. Either way, you'll just see a big build up of ammonia, nitrite and/or nitrate that will kill well, everything.

To test that your aquarium has 'cycled', try 'ghost feeding' your tank. If levels increase quickly and doesn't fall quickly enough, then you know you don't have enough bacteria to handle it. Think about this way - all the food you add into the aquarium will go somewhere. It will either be incorporated into your fish/corals/etc, or consumed by microbes/CUCs, or remains in the water/tank, which may then be removed through some other method. But most will be consumed. So if your aquarium can't handle a bit of ghost feeding, then you're still a ways away.

Doing It Wrong

So now that we have learnt what 'cycling' truly means, we will learn about how people do it wrong.

Let's go through each point of the cycle.

1.) No/not enough bacteria. As we have learnt, bacteria is absolutely necessary. If our tank is too clean, and we don't add any bacteria in any form, the cycle will never run.

2.) No biological filter media. Without any living quarters, there won't be enough bacteria living within the aquarium. Additionally, you run a risk of removing heaps of bacteria when doing water changes and the likes.

3.) No sustenance. If bacteria doesn't have the nutrients they need, then they will never reproduce to numbers that we desire. Many people will only add ammonia, and wonder why they never get enough bacteria. That's because well, there's nothing the bacteria can use to make more of themselves...

4.) Misunderstanding the parameters. It's not good enough just to see an increase (then decrease) of ammonia, nitrite and nitrate. Just because it has went through the cycle doesn't mean there's enough bacteria in there. You should be able to add a lot of food, and see your biological filtration system be able to take care of it. If you see ammonia increase to 0.25ppm, then drop and nitrite increase for a bit then drop, then nitrate for example, then your tank is definitely not cycled. Well yes, actually, technically it is, but remember, we do want to keep more than one fish in the aquarium. We want a large, healthy population of bacteria working their magic.

5.) Timing. If you've been given a specific amount of time to wait it out, you've been given wrong information. Cycling is not an exact procedure. You need to be flexible. If you just wait say, six months and do nothing, then by that time whatever amount of bacteria you've cultivated would have mostly died off. Conversely, if you don't wait until the end of the cycle, there won't be enough bacteria to handle your live stock. Yet, some aquariums cycle in weeks, or even days. We are dealing with living beings after all, and they will take however long they need, not how long we dictate, regardless of what we want to believe.

6.) Water Changes. Yes, that's right. Let's have a long and hard think about what happens during a water change. So firstly, water is being removed. And what is in that water? Waste right? And organics and all that. So wouldn't that be good? No. Let's remember what we are doing. We are growing bacteria. In this case, all that ammonia, nitrite, nitrate and whatever else we have in the aquarium is to feed the bacteria, and so removing it will just reduce the amount of food available for the bacteria to feast upon. That will just slow the cycle down. Everything has to be in context, and in this case what we would normally regard as unwanted, is actually something we do want.

Doing It Right

So how exactly do we do it right? Well, here are some personal opinions of mine, based on the above:

1.) Add plenty of bacteria, and to a multitude of places. Bacteria is (literally) the life source of your biological filtration system, and having them well established all over is great! Plus, obviously when crowded, bacteria, much like any organism, will lose out due to competition. In a specific area with 1000 bacteria, there's a high chance that a number won't get access to sustenance. The same 1000 bacteria, spread all over, will all (most likely) have a chance at accessing sustenance. Eventually as they all grow, it will get crowded anyways. But the question is how quickly can you make it crowded. The answer, if you have 1000 populations of bacteria growing in different places at once.

2.) Have lot's of surface area. Bacteria likes to colonize surfaces, and so they benefit from area, not volume. Having biological filter media with a large surface area (such as live rock or Marine Pure) will be highly beneficial, as that's just more space for colonization, and hence more bacteria growable.

3.) Sustain your bacteria! Like I said above, just adding an energy source is not enough. You need to actually provide sustenance for your bacteria. I like to use seafood mix. Puree it and spread all over the aquarium. Actually that's how I like to introduce the bacteria as well. :D Also, you should ghost feed your tank as it is cycling as well, just to test the waters (literally).

4.) Check your parameters regularly! It is easy to miss a huge spike that would indicate a massive amount of waste, before being consumed by bacteria. Especially make sure to double-check a short while after feeding the tank, to see how much ammonia is produced, and then how much is consumed. One way to do it is to 'feed' your tank even before you add anything to it. That way, you know how much waste is produced when there's no filtration of any sorts, from a specific amount of food. Oh and of course, after the cycle, double-check by feeding some more.

5.) Be flexible. Don't rely on a fixed schedule. Adapt to the changes of your aquarium as it cycles. If it cycles fast - great! Be ready to add your live stock soon (double-checking that there's enough bacteria to handle the bioload, of course). Otherwise, take your time, but always be ready.

Why the Focus on Bacteria?

Why do we focus so much on bacteria? Or in microbes in general?

The fact is this, we have to establish our filtration system properly before adding the first live stock (unless we don't them potentially dying). Whilst most filtration media needs no setup time, others do, and biological filtration media is the one that may take the most time (see 'Setting Up Your Equipments' in this guide). Therefore it is always best to set up the biological aspect of one's filtration system first, before setting up the others. This is especially true if you use dead/dry rock, as that may require a lot of time for microbes to establish.

Which also translates to - just because you have done establishing your microbes, may not mean that your tank is 'cycled'.

As above, the final step is to test your aquarium's filtration capacity. If it cannot handle your 'ghostfeeding', it will not be able to handle the eventual bioload. In which case, the aquarium may be missing some sort of equipment, or that you haven't gone through the microbe propagation phase correctly.

Conclusion

'Cycling' is something that is known to all of us, but is often not fully understood. Whilst eventually most tanks cycle anyways, it is always better to do it right from the getgo. Hopefully, this would have answered some potential questions that people (especially beginners) may have. :)

Remember, most importantly, cycling is not a straightforward, rigid process. You need to know how to adapt and change as necessary, to best cycle your aquarium and get the most out of it.

Once you have added your first live stock, and have no means to remove it, it is hard to improve your biological filtration system.

Product Review: Cermedia Marine Pure 8'x4'x4' Block in a 36L Saltwater Aquarium

Introduction

MarinePure(TM) by Cermedia is a product that has been around on the market for quite a while now, though only recently truly gaining a foothold. There are 3 versions of the product available in the Australian market; the 1.5" sphere, 8"x8"x4" block, and the 8"x8"x1" tile.

There are various differences between the different products. The sphere is in and of itself easier to distribute in an aquarium system, due to its relatively smaller size. Hence, it can be fitted into various areas of the tank/sump, without any modifications.

The tile and block are similar, though the tile is thinner - allowing for the insertion into tighter areas.

The block is harder in regards to placement, and is generally relegated fully to the sump, in contrast to the tile and spheres, which can and do find their way into displays where they are hidden by corals, plants, gravel or the likes. Of course, with a bit of creativity and planning, and/or a bit of modification, the block can still be placed in the display.

A 36L nano with 2 inches of Marine Pure hidden within the sand. The corals sit directly on top of it.

Background

Displayed above is my very own 36L nano. The sand fully hides the Marine Pure block, though I did cut it down the middle (making it 2' rather than 4'). Nonetheless, I am sure with a bit more effort, it won't be an issue. In a large tank, an entire Marine Pure block can be hidden amongst the rock work, for example.

Marine Pure placement revealed! And an Amphiprion melanopus chillaxin' in the corner.

Of course, if you happen to own something that loves to dig, prepare to have the block revealed (assuming you hid it in the sand). Here, my Amphiprion clarkii (not pictured) has decided to completely excavate the corner of the tank and reveal the Marine Pure. It is interesting to note that being the same color as the sand, it isn't quite that conspicuous.

Hidden in plain site. Can you actually tell the surface of the Marine Pure block from the sand?

But the ability to be incorporated into the display (or otherwise, in the case of the block), is just one of the factors to consider, and I personally care about the capabilities of the product.

Whilst all Marine Pure products (the spheres, tiles and blocks) are capable of denitrification, the blocks are said to be naturally better at it, thanks to the size and therefore deep, hidden compartments within. Most denitrifying microbes (not all) are anaerobic, therefore preferring/requiring anoxic environments. Therefore, it is recommended to place Marine Pure blocks (where you want denitrification to occur) in low flow areas, minimizing the amount of oxygen brought into the rocks. That or in the sand. This is why I placed mine in the sand.

I did cut out a 4'x4'x8' piece to place in my sump though.

Top view of the Marine Pure placement. The smaller, irregular piece sits on top of the 4'x4'x8' piece that takes up an entire compartment of my sump.

The placement here is essential for my build, as most of the flow is over the top of the divider. However, a slower movement of water does go under and up through the second chamber, which takes advantage of the anaerobic microbes within. The slow flow means less oxygen being driven through the block, but still enough to bring waste through it.

As a Biological Filter Media

So why all this talk about microbes, water flow and conditions of oxygen?

Marine Pure is a biological filter media. Amongst the scheme of filter media, Marine Pure is regarded by many as the most effective of them all. Between the three different categories of filter media - mechanical, biological and chemical - the biological media is the one that is regarded as the most long lasting, as it simply acts as a home for microbes that break down waste, the same as what happens in nature. Whilst mechanical filter media can be rinsed out until it is ruined, chemical filter media cannot, in any way, be rejuvenated.

The advantage of Marine Pure over other types of filter media is two-fold. The first advantage is that it does not degenerate, at least not as quickly as many other types of biological filter media. Ceramic noodles for example, can break down after 3-6 months of use, releasing tiny bits of itself into the water. The same can be said for many other biological filter media.

Live rock, the 'natural' biological filter media, do not suffer from such decomposition, but is not as porous as Marine Pure, which therefore is not as effective. It is often suggested that 30 kilograms of live rock is required for a 300 litre tank, whereas one block of Marine Pure can do the same.

Therefore the filtration capacity in my tank is in theory equal to 30 kilograms of rock. As for it's life expectancy, unlike many other biological filter media, there does not seem to be a point in time whereby the Marine Pure breaks apart.

Observed Results

At the beginning of the setup, I carried out an experiment whereby I added pureed marinara (seafood) mix in an attempt to completely go overboard with organics. I added approximately 20g of marinara mix in total, and within a day, it had pushed ammonia levels off the charts. The test kit couldn't even register how much ammonia is there, and the color change was something that I have never even seen before!

Within two days though, the ammonia levels have gone down considerably, closing in on zero. It was at 0.25ppm. The next day, it was gone.

No doubt, the sand would have helped as a biological filter media, but I can't help but attribute most of this to the Marine Pure. I do believe thanks to its large surface area that a lot of microbes managed to establish in a short time.

As for it's filtration capability post-cycle, I have a total of five fish, one large hammer and various corals in the tank. I worked out that I was feeding my fish 10x the amount recommended, and my corals 26x the recommended amount. Oops. Well the pictures above was taken when this was happening, and when I measured my parameters, well amazing, there was undectable ammonia, nitrite and nitrate.

Conclusion

Marine Pure is a highly effective, long-lasting biological filter media. The block is not cheap ($119.95 retail in Australia), but that's 95% less expensive than 30kg of live rock anyways. It lasts indefinitely as well, or at least that seems to be the case.

Here are my ratings for the product, out of 10:

• Price: 9, it costs quite a bit, but is sure worth it.
• Efficacy: 10, works wonders.
• Longevity: 10, for now anyways.
• Appearance: 7, it has a clean look to it, but may not fit in any tank.

Overall: 9, it is a solid (pun intended) product, that offers just so many benefits. I have found nothing that comes even close. Although it does cost quite a bit, it is an one-time purchase after all, and spending $199.95 per 300 litres of tank water isn't too bad. The only true issue in my opinion is its looks, but then again, with water circulators and all that in our tanks, it's not as if it matters too much if it looks 'artificial', eh?

Notes

-In Australia, Marine Pure can be purchased from most stores. Online, it can be bought from reputable sites such as Majestic Aquariums and Age of Aquariums.

-The distributor and supplier of Marine Pure in Australia is Majestic Aquarium's sister company, Aqua Premium. If you are a shop and want to consider distributing this product, contact Aqua Premium directly.

-Since this post was made, I have been told that this product seems to disintegrate at a low enough pH (at around 6.0). If anyone have anyone has conclusive results for this (tested it, found it to disintegrate at a certain pH/over a certain amount of time), then please do let me know by commenting below. I would love to know more about this. So far though, it seems to be safe at least at a pH of 7.0, so for reef tanks the Marine Pure products are at least still entirely viable.