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New Tank Syndrome

Question: I hear the phrase "New Tank Syndrome" what is it?

Answer:  New Tank Syndrome is that difficult period when a tank is setup for the first time, often by newcomers to the hobby. They are often discouraged when it seems that nothing is going right for them. Fish are dying for no apparent reason, water is cloudy and smelly and everything is covered in green algae. This is New Tank Syndrome, not just some old wives tale, it's very real.

Those who preserver will find that after a few weeks things start to settle down, but just when things seem to be getting better all the fish get white spots, Ich (Ichthyophthirius multifiliis), and start dying again. If you're quick and get some treatment some of the fish will recover. Shocked that you have a disease in the tank in your tank you set about cleaning and sterilising everything, the tank, the gravel, and most of all the dirty filter. Satisfied that you have eradicated all traces of disease and bacteria you go to bed with a quiet confidence that nothing could have survived your clinical onslaught. Refreshed you get up next morning to find all your fish are dead..! Sound Familiar?

What can you do about it?

First of all you must understand what is happening and why..! Remember when you bought your first fish and we recommended that you only put in a couple of fish to start with and feed them very sparingly? The reason for that is simple, Fish produce waste in the form of ammonia through urine, faeces and directly via their gills as a result of respiration, and the more you have the more ammonia they produce.

Bad news is, Ammonia is poisonous to fish and the higher the level the greater is the effect on the fish. Good news is, in nature there are Bacteria which just love to feed on ammonia and convert it to Nitrite. More bad news, (a) these bacteria need time to establish themselves in sufficient numbers to process the waste produced by your fish, and (b) Nitrite is also poisonous to fish.

All is not hopeless however. There is a second strain of Bacteria which feeds not on Ammonia, but on Nitrite, and converts it to a less harmful Nitrate, a plant fertiliser. As before, this Bacteria needs time to multiply, but once established can convert all the harmful Nitrite, to Nitrate.

So how and where does all this take place, and how long does it take? The answer is in paragraph 1, "after a few weeks things start to settle down". As the Bacteria start to colonise the medium inside the filter they grow and multiply quite quickly, and after 3 - 4 weeks are in sufficient numbers to handle the waste from you initial couple of fish. If you now add a few more fish the numbers of Bacteria will increase quite rapidly to handle this additional waste, and everything should stay stable.

So can you see a pattern emerging here? Too many fish at the start, and being overfed, (all beginners overfeed their fish). At this stage the filter is useless and the Ammonia levels rise to such an extent that the fish die. The excess food and waste pollute the water and it turns the colour of Mrs Campbell's Chicken Broth. When the filter does eventually start to process the waste it produces so much Nitrate, (fertiliser), that the green Algae goes crazy and covers everything.

Stage 2 also has a logical explanation. Ich (White Spot) is caused by a parasite, which while present in most water, normally does not effect healthy fish. Your fish however are far from healthy. For weeks they have been swimming around in a soup laced with two lethal poisons, never mind being netted, transported in plastic bags, dumped in a strange tank and continuously stared at by total strangers. Its no wonder they are weak and stressed and susceptible to the first disease that comes along.

The final straw is of course YOU, the owner. In your mad panic at the mention of the words disease and infection you revert to Granny's old teaching that 'Cleanliness is next to Godliness' and sterilise everything in sight, including the beneficial bacteria that you have spent weeks cultivating in the filter. Now that you have probably added some extra fish to the tank the result is catastrophic. Overnight the ammonia rockets to extreme levels and the fish die in just a few hours. Worst of all, you have wasted time and money, not to mention killing innocent fish, and are probably so discouraged that you give up fish keeping for good.

So what's the answer, can all this be avoided?

In a word, "Yes", take your time and add a few fish at a time, and don't overfeed..! Once your filter is established it will work 24/7 to keep your water clear and your fish healthy. And all you have to do to keep it that way is to periodically rinse the sponges in some water which you have removed from the tank during your routine water change. Remember.. never wash your filter sponges under the water tap, you'll kill all the useful bacteria and go right back to square 1..!

Maroon Clownfish in an Anemone