6 Misconceptions About The Initial Cycle

Introduction

Cycling is a process that we all have to go through when setting up an aquarium. But do we know what is the right way or not? Look at the misconceptions below, and see if you have been doing it right all along!

1. Ammonia, nitrite and nitrate must rise and fall in turn

This is a common misconception, stemming from the belief that there must be an increase of each before the specific microbe breaking down said chemical starts to grow, breaking it down into the next in line.

This is false, as one can start an aquarium with different levels of each type of microbe, sometimes much higher than expected.

For example, ff you use live rock, and it happens to have a lot of nitrite-reducing bacteria, you may see a lot of ammonia and nitrate from the beginning, and little nitrite.

2. The tank is definitely cycled when all parameters zero (perhaps beside nitrate)

This is definitely not true. The initial cycle (also called the bacteria/microbe propagation phase, or BPP/MPP for short) is where you are trying to establish a large amount of microbes to break down waste.

Think about it, in a sterile tank with nothing but salt water, you can measure zero everything. Does that mean that it has cycled? Nope...

On the other hand, even if you measured some PANN (ammonia, nitrite and/or nitrate) and it takes a few weeks before it all zeroed, you still may not have cycled your tank either. If you think about it, the fact that it took so long for the chemicals to deplete (especially if the amount was low to start off) means that you don't have that much microbe to break down the chemicals in the first place. And that also translates to your cycle not being done, as there is not enough microbe to handle the eventual bioload.

A cycle is only done when your filtration system can handle the bioload you will introduce.

3. Only ammonia and nitrites need to be zero

This is one of those 'it depends' situation, but really the answer should be 'no that is not true'. You should have planned for phosphate/nitrate removal, which may be through water changes, or having chaeto in a fuge, or through chemical dosing, or whatever.

But it is not enough to go 'yeah some nitrates/phosphates is fine'. You have to have a plan ready for them. And implement them when necessary.

4. Only ammonia is needed to kickstart a cycle

Besides the obvious fact that you need microbes present, you also need to feed them. After all, matter don't just spontaneously appear. It has to come from somewhere.

So if you want to propagate microbes (i.e. have more of them), then those new microbes must be built from something. And that is from all sorts of molecules that comes in the form of organic matter.

Doesn't matter how you supplement that - through addition of fish food, raw seafood, die-off or whatever, the fact is that it is necessary.

Of course microbes can, as a whole, convert simple molecules in the water (CO2, H20, etc.) into more complex molecules, but it is faster to provide the more complex molecules right away.

5. Cycling takes 'x' amount of time

This is a very lazy, unhelpful suggestion.

There is no set amount of time for a cycle to complete. It could be days, weeks or months. Fact is, it depends on how you are cycling your tank and your tank's specific conditions.

You can wait for ten years and that tank with just saltwater won't cycle.

So don't think all you have to do is wait a certain amount of time, as that is very lazy. That will get you nowhere. Put in the effort to cycle your tank, and be prepared as it can be done anytime.

6. Do plenty of water changes to lower PANN

Again, no. You are just tricking yourself.

The point is to have a filtration system and maintenance schedule to lower PANN. If you are just doing massive water changes to lower PANN during he cycle, then obviously PANN is not lowering due to your filtration system.

Unless you will maintain the same large amount of water changes as part of your maintenance schedule, in which case it's cool.

The only situation where you may want to do a lot of water changes is if there are lifeforms in the aquarium you want to keep during the cycle. In that case, water changes are needed to keep PANN low enough for them to survive.

Conclusion

These are six common, persistent misconception that you must avoid, or else you'll run the risk of not cycling properly, and running into problems down the track.

Good luck and have fun reefing!