Cardiff Aquarium

I recently re configure my tank after the move. I had the tank set up for a fortnight and test the water all be fine. Then my sister's fish from London to Cardiff, they were put in my tank there was no infection of the disease with one of them, they were a community tank and within 24 hours they were all dead. I re tested the water after all is normal. the filter was cleaned from the tank temperature was 26.4 fish eyes became white with pastry. and they remain faithful to the camera angel fish survived, but after a few hours he was dead and stuck to the heater. I lost all my sisters fish amounting to 16 fish. Can someone tell me what's wrong as I want more fish. HELP!

You must have cleaned the tank with something toxic or water heater may be broken and make the water too hot. Did you check the temperature of the water tank? Could the heater was broken and cooked the fish alive. They would have died anyway because you cleaned the filter for some reason. This would have effectively destroyed all the good bacteria and adding 14 lol fish, which are sad. Ya anyway I told the broken radiator or was too high and killed em or a chemical has been introduced from cleaning that is toxic. Anyway lesson learned, Good Luck

Edit: Whats a fortnight? Is 14 days? This must be some slang huh Europe. Well, if so, then yes, they do not die from a peak of ammonia as Dark Said.

If it was the shock, they wouldve died instantly. 14 days isn't long enough to cycle a tank. They are dead because you didn't do it. Basically, a peak of ammonia killed them.

Perhaps they have been electrocuted

There are two things that came to mind your fish kill. It could be that heat does not work correctly. The water heater must be regulated to switch on a tank of cold water at a temperature of 75% f and when this temperature is reached, and when the water reached that ... it should go.

When you put the fish in water that is fresh, it is likely that the fish swim up the heater for warmth. If there is a lot of them, the closer the heater is blocked by the other and closer to the heater can not swim and burn.

Remember the water tank should be 75-78% f before putting fish in.