At this one chinise restraunt near our house there is a fish tank. there are about 6 comet goldfish. It looks like it is about 120 gallons. Even though it is not very overstocked or not overstocked at all. The tank is nasty!!!! It is a very dirty tank!!!! i doubt they have every cleaned the tank. they might have a filter. there is a wood collom that a hose goes into and a other hose pours water out. But it might be a filter or it might be airating the water. still the gravel is very messy. the water looks like poop!!!! I asked my parents if I could give them a piece of mind. But they said that I could not. I would be happy to do weekly cleanings for free if they let me. not for them just for the fish. My friend is getting a 30 gallon tank. i am teaching him about fish. I recommended convict cichlids and angelfish. I also told him that he could get 1 BP. i tell all my friends that like fish to not trust the petsmart people. most petsmart people now nothing about fish. well some do. the one at my Local petsmart is OKAY with fish. She does not give the best advice. But it is better than some other fish department people.