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i got a new tank just over a week ago and have had 2 dead fish since then. i bought 2 goldfish and a placatomus. Both goldfish seemed really active at petco but when i brought them home athene was very lathargic and didnt seem too anxious unlike apollo (who we later figured out has a special back fin and a sort of limp but seems to swim/eat/poop fine) well the next morning athene was dead on the bottom of the tank just laying there. my mom said that she had a white color film on her side. i went to walmart and bought some quickcure and another goldfish and a black moor. I also tested the ph level and it was about 7.6 which the box said was about ok for fish. two days later the new goldfish was found dead trapped under the filter (not in though). We bought some tablets that were supposed to get rid of ammonia, correct ph level, and condition the water. I changed about 20% of the water put some tap water conditioner i bought and put the tablets in the tank. Today i thought poor little apollo was dead because he was flipped over. He was struggling to keep him self upright and was visually very upset. I checked them at lunch and apollo was doing much better and upright but still swimming on the bottom not very happy and the ares the moor was kind of lathargic and and just staring out the glass of the tank. He's also been having large thick poo that follows him around a bit. I feed them flake food that i soak in water before hand. please help any advise ive read alot of stuff and not eveything matches up and i feel like im guessing on what to do or doing too much =(