i'm pretty new to fish. I had a very small tank with a couple of goldfish but they died and every time i tried to get new ones the same things happened. so i gave up on goldfish. now i have 2 tadpoles in the small tank and i have a 20 gallon tank with alot of tropical fish. including a couple mollies and a swordtail, one of my mollies was pregnant and i think she was ready to burst tonight but all of a sudden she started flipping out and just sat in one spot and died. i dont know what happened. the levels were fine, she seemed ok. she kept staying at the bottom of the tank for long periods of time, almost like she was resting then went to the top a lil bit. no frys ever came out that i saw, it looked like one was on its way but thats when she freaked out and died. if anybody has any idea what happened please help me out! also how many fish should be in a 20gal tank? we have alot of little tetras and alot of other types of fish, they are all doing fine right now but i dont know if we'll need a bigger tank later on. please i need advice!
