I have a 38 gallon fresh water tank. I have a pleco, an angel fish, 2 gouramis, 2 platys, 5 neon tetras, 4 cobra guppies, a balloon molly and 3 black mollies. Ive had the tank for about 6 weeks. Just tonight I added the guppies and another balloon molly to go with the other one. As soon as I put...