Platy seems to be struggling
So randomly last night I noticed my platy would just fall to the bottom of the tank and softly curl. When she wasn’t doing that she was attempting to swim to the top and gasping for air, or kinda just swimming low to the tank. Checked my levels and everything is completely fine, moved her to a hospital tank and did a 50% change for good measure on the main tank. None of my other platys or guppies are doing this? I got an oxygen stone just in case last night and should be here today, in the hospital tank she is moving much more and not doing the curl but still gasping for air. Help!