ok so i lost a platy today. she stopped eating 3 days ago and now has passed on. all of a sudden one of my older guppy females is swimming fine but when she stops swimming her tail floats above like its filled with air! what is going on here? is she just old? is she suffering from something??? she gave birth to about 13 babies a week ago so i dont think she is experiencing stress. ive done daily water changes. i dont have the money to get aquarium salt(until next wk anyway). would table salt hurt them? i dont want to hurt my fish. please help!!!