Why is my platy’s stomach so big??

I have my three platies (2 females 1 male) for almost three months now, but the golden one’s stomach is getting so big compared to before and others. I originally thought she is pregnant but she is being like that for almost 2 months now... I also noticed some “wrinkles” on the back of her stomach... so can anyone have similar situations or know what happen?

 

How big is the tank? What fish are in it? How much do you feed them?

 

My tank is about 1.5 gallons, and I have three platies in it. I feed them twice a day, not much I think. My two other platies look fine, just this golden one is strange

 

If you can, I would upgrade to a 10 gallon. Platies are livebearers which means they don't lay eggs and breed like CRAZY. Try fasting them for at least 3-5 days and when you do feed, feed only a pinch.

 

Ok I will try that. Thank u!