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30 Aug 2014

How To Cycle A New Fish Tank

Posted By : Guest

Filed Under : Aquatics | Tropical Aquariums | Fish | Marine Aquariums

When researching your new fish tank, a phrase that is bound to come up is Fishless Cycling. It’s not a phrase with the most obvious meaning (especially to a novice), so finding out what it is, how it works and why you should be doing it can be a little daunting.

New Tank Syndrome

Before you can properly understand Fishless Cycling, we need to take a look at New Tank Syndrome, the solution for which is often referred to as Fishless Cycling.

New tank syndrome often refers to the problem faced by most tanks shortly after set-up, where the tank has insufficient cultures of beneficial bacteria present within the filter and live rock/substrate to deal with the increased ammonia levels caused by the fish in the tank.

Ammonia is present because it is expelled by your fish as waste bio-product,eg excrement etc. High levels of it can be really bad for your aquarium, burning your fish’s scales due to its alkaline nature, inhibiting your fishes ability to respire and can lead to fish death on a large scale, potentially killing all the fish in your aquarium. On top of that, it is like a fertilizer for algae blooms, causing your tank to turn into pea soup!

Putting fish into a brand new tank before sufficient amounts of beneficial bacteria can develop in the filter means that there is too much ammonia in the water to be dealt with by the small quantity of bacteria present. Many an aquarist has bought an expensive set of fish only to lose them quite horrifically just a few weeks or months later because of this problem. But there is a way to deal with it: Simulate the fish!

Fishless Cycling

Most aquarists would agree that this is the best way to kick-start the nitrogen cycle within your tank – that’s the way that ammonia is turned into Nitrites by Nitrosomonas Bacteria, and then relatively harmless Nitrates by Nitrospira Bacteria.

By adding ammonia slowly into your tank water, you can simulate the ammonia creating by your future fish, giving the cultures of bacteria something to feed on, turning it into nitrites, then nitrates which are far less damaging to your tank environment. This can then simply be removed with regular water changes.

Step By Step

Here is the basic guide to fishless cycling, bringing you closer to a more mature tank that can handle the beautiful fish you have been dreaming of:

Basic Setup: Set up your tank as your would wish it to look, adding de-chlorinated RO water and setting the filter running. Leave it for around 24 hours to ensure that the filtration system is operating well and there are no leaks

Add some ammonia: Calculate the amount of ammonia needed to kick start the cycle by reaching around 2 to 3ppm (parts per million) and begin adding the ammonia. You can use an ammonia test kit to get reliable readings on how this is coming along. Adding the ammonia gives the beneficial bacteria something to start eating, turning it first into nitrites (even more deadly than ammonia!)

Ammonia begins to drop: After 24 hours you should begin to see a drop in ammonia levels – keep testing, it isn’t finished yet, so watch for spikes and drops. Add a little more ammonia to bring it back up to between 2ppm and 4ppm again. Nitrite levels should be very high at this point, and again, you can watch them with a Nitrite test kit.

Nitrites begin to drop: Nitrites will now begin to drop as well as the cycle continues, finally giving you a relatively harmless Nitrate reading which can be dealt with using regular water changes.

Keep going: Your tank is going to take time to balance out until you have 0ppm readings for ammonia and nitrites and they are stable at that level. For an average tank, this is going to take around 4-8 weeks and you should only consider adding fish once you are confident that these levels are stable.

Add some fish! It’s about time too! It may have taken a long time, but by fishless cycling you have done the right thing for your tank and fish. Here are a few more handy tips for fishless cycling…

Tip #1

You can get all-in-one test kits that can handle nitrates, nitrites and ammonia levels instead of buying them all separately. It can sometimes work out cheaper this way!

Tip #2

A pearl of wisdom that has been floating around the aquarist world for a while often has a lot of truth to it: Good fish keeping is really about good water keeping – keep your water chemistry in check, including ammonia, nitrite and nitrate levels, and your fish will be able to look after themselves and just require feeding.