Fish, Tanks and Ponds


Fish, Tanks and Ponds
A comprehensive guide to fish

New tank syndrome

Fancy goldfish
Fancy goldfish

What happens when you set up an aquarium?

Once all the equipment is in place and the water has been added everything will look very clean and clear, even if you carried out some water tests the results would show that there is no ammonia or nitrite present. This seems ideal for the fish but this is far from being the case.

Within twenty four hours the tank will most probably go quite cloudy, this is normal and nothing to worry about. The cloudiness is caused by a proliferation of bacteria in the water column which have multiplied rapidly and to exploit all the nutrients in the water. Within a few more days the water will clear of its own accord provided that you don't do anything.

To move on to the next stage ammonia will have to be added to the tank, simply leaving the tank to stand without adding any ammonia or a source of ammonia for a week, three weeks or several months will achieve nothing regardless of the time it is left.

How to prevent new tank syndrome?

The only way to prevent new tank syndrome is to cycle or mature the tank before any live stock is added. This article isn't about cycling a tank so I won't go into to much detail but full details on cycling here but here is a brief outline. To begin the cycling process you need to add either ammonia or a source of ammonia. There are three basic ways to do this

  • Add some household ammonia.
  • Add some fish food or a piece of prawn, fish ect which will eventually break down and produce ammonia.
  • Use a commercial product which adds ammonia in a precise way and comes with full instructions.

Once ammonia is present a particular species of bacteria will begin to colonise the filter and they will oxidise the ammonia and turn it into nitrite. Soon all the ammonia will be turned into nitrite as soon as it is produced and the cycling process will be partially complete.

Nitrite is still very toxic to fish so it still isn't safe to add any livestock just yet. Once the ammonia has disappeared and the nitrite level has risen another species of bacteria will begin to colonise the filter and every other available surface in the aquarium where there is fresh well oxygenated water.

This second species of bacteria will oxidise the nitrite and turn it into nitrate, once these bacteria are present in sufficient numbers the nitrite level will start to fall and when your test kit no longer detects any nitrite the tank is cycled.

The tank will continue to mature over the next few months and it will be fully mature between six to twelve months, before this happens all livestock should be added slowly so that ammonia and nitrite spikes are avoided.

How to deal with new tank syndrome

Unfortunately people are still sometimes given poor advice and told that if the tank is left to stand for a few days it will be safe to add fish, IT WON'T and this is when new tank syndrome is most likely to occur.

After the fish have been in the tank for a few days the ammonia level will have risen because the fish are a source of ammonia and there aren't enough bacteria present to breakdown this ammonia although these bacteria will begin to colonise the filter now that ammonia is present.

This ammonia could injure or even cause the death of the fish if nothing is done to prevent it.

  • The fish may become listless
  • Gasp at the surface
  • Develop red streaks in their fins
  • Bleed from the gills
  • Eventual death

The pH of the water will make a difference if ammonia is present because ammonia becomes more toxic as the pH rises. If ammonia is present there are two courses of action which will help, Make a water change to lower the ammonia to no more than 0.2 ppm and periodically test the water and make more changes if it rises again and secondly add a product to the water such as AmmoLock which will reduce the toxicity of the ammonia but the ammonia will still show on water tests.

Nitrite poisoning

Nitrite prevents the fishes blood from carrying oxygen, this leads to:

  • Lethargy
  • Tissue damage from what appears like bruising to ulcers

The fish will be very stressed and this might lead to secondary infections such as white spot.

Adding a tiny amount of salt will help protect the fish from nitrite poisoning.

It is important that you don't overdose the salt because adding more won't help and may do harm.

As with ammonia make the necessary water changes to keep the level of nitrite below 0.2ppm and keep it there.

Other things which will help are:

  1. Stop all feeding, the fish won't come to any harm because of this and it will help to keep the level of ammonia/nitrite to a minimum.
  2. Keep the tank and especially the gravel very clean.
  3. Monitor the water quality and make water changes as and when needed to keep the levels down to an acceptable level.
  4. Increase aeration.
  5. Don't add any more fish until the tank has cycled.
  6. If you have a fish keeping friend try to get some filter media from a mature filter and add it to your filter, this will greatly speed up the process. Adding water from a mature tank will do little if anything to help because the bacteria that are required colonise surfaces rather than the water column.
  7. Use an ammonia locking agent such as AmmoLock if ammonia is present or salt using the calculator on this site if nitrite is present and remember to add one of these to any new water when making water changes.
  8. If the fish have reached a stage where they have ulcers due to nitrite poisoning you can treat them with the appropriate medication.

USE A SEPARATE CONTAINER to do this because methylene blue harms filter bacteria which is the last thing that we want to happen at this stage. Methylene blue will protect the fish from secondary infections but more importantly it will speed up the release of new red blood cells which will help the fish to heal.

What is new tank syndrome?

New tank syndrome as its name suggests is a condition which mainly but not solely new fish tanks. It occurs when there is insufficient bacteria present to cope with the amount of fish stock in the aquarium. The bacteria needed to breakdown all the wastes produced by fish take several weeks to colonise a new aquarium and if fish are added before the bacteria are present in sufficient numbers then the levels of ammonia and nitrite will rise, when this happens the tank is said to be suffering from new tank syndrome.