Hi my boyfriend and I just recently started up a fish 20 gallon tall fish tank. The tank is a week old. Of course we got to the store and got over excited so I've been told I've overstocked. ( 3 big yellow neon fish, 2 black mollies, Dalmation Molly, pale blue gourami, dwarf gourami, catfish, sucker fish, 2 snails, 2 African dwarf frogs, and 2 ghost shrimp. ) I eventually want to upgrade to a 40 gallon because well my fishes will be growing of course ( if I don't screw up too much lol) I have 100 watt heater and a tetra ex20 whisper power filter. I have an extra top fin 20 filter I've been thinking about adding but I don't have the part that holds the actual filter. Not sure if I can buy a replacement. I've been using distilled water and I just looked up and I've read that's bad? So I went out and bought API stress coat for future water changes. I plan on doing a 50% water change tonight. I've been having a bit of a problem with ammonia and I think some of my fish are showing signs of ich.