Fish Tank General Question?

Hello :)

Too many fish and not enough room in your tank. You need a 75-125g for all the fish you have. Minimum is a 75g tank.

You are overcrowding your tank. Each fish grows 8-9 inches. The first goldfie should have 30g and each additional 15-20g. No matter how much filtration you have your nitrates will always be high. I try to have my nitrates bellow or at 20ppm.

Re-home your fish. I have 3 telescopes in a 55g and no more. These fish get huge and in a crowded tank they get sick very easily.

Have you checked your water?

API makes good liquid testing kits: http://www.apifishcare.com/aquarium/water-testing/...

You at least need the ammonia, nitrite, and nitrate testing kits. You may have a cycled tank, but your nitrates will be really high. Over 40ppm of nitrates is toxic to fish. Get your water testing kits and test your water.

If you do not believe us here (plug in your numbers): http://www.aqadvisor.com/

Filtration can be over 100%, but if stock is over 100% you are overstocked and need to move fish around into a bigger tank. Having an overstocked tank is not a good idea mate.

Get what your fish need and get them a bigger tank. At least a 75g-90g tank. You might have to upgrade again. The bigger the better. For your 30g you should only have one and that is pushing it.

You need a Bigger tank for all those Goldfish at least 100 gallons and ideally a canister filter with double filtration .

goldfish are very messy fish and produce plenty of waste. your filtration is iffy and goldfish do not need a heater. i would suggest you do more water changes and upgrade to a minimum of a 55 gallon tank. a 30 gallon could have two goldfish at the most.