I have a molly that recently gave birth for 11 new baby fry (all of which are doing phenomenal and thriving), and now it seems like she is about to croak and I'm hoping to avoid this. She's in my 30 gallon tank with two other molly's, one female and another male, 2 guppies and has been swimming oddly. Her head is always facing down, and she has trouble swimming in general so usually stays at the top or bottom of the tank. Is this swim bladder disease, dropsy, and is there anything I can do for her?