Why do I need to cycle my goldfish tank?
The number one cause of goldfish death in the aquarium hobby is due to ammonia and nitrite poisoning. Usually someone will decide to start an aquarium, buy all the equipment, set it up and then add the fish.
What happens over the next few weeks is a natural biological process we call ‘fish tank cycling’. During the cycling process ammonia and nitrite levels rise to toxic levels and naturally occurring nitrifying bacteria establish themselves to begin processing these toxins.
During these weeks if goldfish are present in the tank they are exposed to these toxic levels and for many fish who are already not in their best shape coming straight from a fish store, the experience is too much and they die.
Avoiding goldfish deaths from the cycling process is quite easy to do and requires little more then some patience and a inexpensive water test kit, which you should stock anyway for the long term health of your goldfish tank.
What is ammonia?
Ammonia is the byproduct of fish waste. Goldfish (and all other types of fish) release ammonia into the water through biological release. There’s no way to stop them doing it so in the aquarium hobby we have to manage ammonia levels and bring them down to 0.
Ammonia even in small concentrations is toxic to fish and can often lead to ammonia burn which presents as areas of black on the fish. Obviously not to be confused with your goldfish’s natural coloring.
What is nitrITE?
Naturally occuring bacteria will eventually establish themselves in your aquarium and start to process the ammonia your fish are producing. They feed off this waste and convert it into nitrite.
Unfortunately nitrite is even more toxic to goldfish then ammonia and also needs to be managed in our aquariums and kept at a 0 level.
What is nitrATE?
Nitrate (not to be confused with nitrITE) is the end result of a toxin conversion process in your tank that occurs naturally. A second set of bacteria will also establish themselves and feed off the nitrite produced by the first set of bacteria processing the ammonia. The end result is nitrATE and thankfully it’s nowhere near as toxic to goldfish as the first two toxins.
If left unchecked though it can be harmful to your goldfish. Usually goldfish keepers remove nitrate with regular water changes or by keeping plants which then naturally convert nitrate into plant matter.
So what does cycling my tank have to do with any of this?
Cycling your goldfish tank is to allow these natural bacteria to colonise your filter and grow large enough to process the waste your goldfish will be outputting. When you start up a tank no bacteria is present and it can take a month to two months for the bacteria to establish themselves.
If you add your goldfish from the start your essentially exposing them firstly to toxic levels of ammonia until the ammonia bacteria get it under control, and then again to toxic levels of nitrite until the nitrite feeding bacteria colony grows large enough.
This is a huge unnecessary risk to your goldfish and even if it survives the effects can be permanent and your fish might not live as long as it might have.
Thankfully as I mentioned at the start of this article cycling your goldfish tank before adding any actual live fish is an easy and inexpensive process. Next weekend I plan to cover the fishless cycle; how to do it, what you need and roughly what you can expect from the experience.
It’s also important to acknowledge that a lot of people don’t realise what cycling a tank is until they’ve already set everything up and bought fish. For this reason I’ll also cover what to do if you’re unavoidably caught in a cycle with your goldfish sometime over the next few weekends.
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