Strange behaviour In my fish tank.
In my tank at the moment I have some platies and danios. The last 2 days ive watched some strange behaviour ive never seen with fish before ? maybe its just a platy thing but I don't know. Well first i noticed one of the pregnant females doing back flips like she'd swim up to the corner of the glass then sort of back flip off it and she would do this over and over then sort of go into a spazum and carry on doing it again and again. I watched for a while and then she stopped but after that one of my zebra danio females started doing the same thing in the same place (?). Today when i came back from work i went to feed them as normal and ive noticed one of the males (100% sure its a male) is huge like fatter than the pregnant female ? it looks like hes swallowed a marble, why could this be ? Then i noticed one of the other female platies doing the same back flippy thing in the corner today ?