Molly swimming vertially and seems to have changed shape - Male dalmation

Question
I have had this tank for approximately 2 months.  It has two dalmation mollies (1 male 1 female).  2 Platties, a bottom eater fish, and two garamies.  about 2 weeks ago the the male dalmation molly was sitting at the bottom a lot and seemed to be injured.  No fungus apparent.  He looked to have injured fins.  He healed and began simming up and down.  However, now he looks deformed, he swimms vertical a lot and has either destended abdomen or a hum on his back. PH is fine and he is eating fine.  Help -- is Arthur ok?

Answer
Hi Chris;

Make a 25% water change and do it at least every week. Vacuum the gravel every 2 to 4 weeks. Mollies require very clean water and need veggies in their diet too. Offer them spirulina, romaine lettuce, cooked green beans, cooked peas, squash, etc.

The break-in period makes toxins rise to pretty high levels sometimes and some fish are affected more than others. Your tank is just coming out of the break-in period. Depending on how many fish you have and how big the tank is, the levels may have gone too high for him to tolerate. Not every fish responds the same way, some of them are just more sensitive than others. So do the water change, change their diet and see how it goes.

Watch to be sure he isn't being picked on by the other fish. If so, he needs to be isolated for his own safety.

I hope he turns out okay.....

At Your Service;
Chris Robbins