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"New Tank Syndrome" &
"The Nitrogen Cycle"

No, they are not the names of two of the latest bands to hit the charts. New Tank Syndrome refers to a few events that occur in an aquarium during the first few weeks of being set-up, or after an event that destroys certain bacterial populations in the tank. The problems that can arise are mainly due to your fish’s waste products building up to quite dangerous levels. This can result in the fish being poisoned by their own excretions. These same toxic compounds are also created when uneaten food is allowed to build up in the aquarium.

Symptoms of this poisoning are that the fish may sit around on the bottom of tank looking listless. They may also sometimes be at the surface of the aquarium breathing rapidly so that they look like they are "gasping for air".

If you see this sort of behaviour in your fish it is important to perform a water change to dilute the toxins.

Obviously there is something at play in an established aquarium that allows us to keep fish alive long term, or else all of our fish would just keep poisoning themselves all the time. What happens in an aquarium over a period of time is that certain species of bacteria build up which neutralize the more toxic forms of the fish’s wastes. The most toxic of the compounds that are produced by your fish is ammonia (NH3). Ammonia is lethal to your fish in as low a concentration as two parts in every million.

Ammonia is broken down by a species of bacteria that converts it into Nitrite (NO2). Nitrite is far less toxic than Ammonia is, however it is still not a pleasant thing for your fish to swim around in. Nitrite is toxic at levels of around ten parts in every million.

Nitrite is broken down into a relatively harmless compound called Nitrate (NO3). It is important to keep this compound down to levels of less than 30 or 40 parts per million though, and this is done primarily by water changes.

The process of bacterial colonization takes around three weeks to establish fully, but once it has, it is important not to wash the gravel of the aquarium with tapwater, or allow the filters to be shut off for too long as both of these will cause the loss of large numbers of the good bacteria.

Remember, a slightly dirty aquarium is a healthy aquarium, but keep those water changes happening

If you have any questions about this please don’t hesitate to ask one of us.