Hello all. I'm having some problems with platies. This is a long post but I've tried to include as many details as possible so you can help if you can. Last week I purchased what I THOUGHT were 2 females and one male (the store only had two females). My plan was to put the platies in my 2 gallon, take the fish from the 2 gallon (1 Betta and three albino cories) and put them in a new 5-gallon Hex. I was going to take most of the filter media from the two gallon and use it to jump-cycle the 5 gallon. BUT when I got home, there was a plumbing emergency and I had to shut the water off to the house. I ended up with all the fish in the 5 gallon and no two gallon QT tank because I didn't have the water. Next, one of the "females" began to chase around the other platies. I looked closer and found an underdeveloped gonopodium that could pass for a female's anal fin, so it was actually a male. Now my tank actually had 2 males and 1 female. The two males started chasing each other and the female. The other male started nipping at my Betta's tailfin and the two of them got into it. By now I had water, so I started up the 2 gallon and put the Betta back into it. But all of the platies started intermittent flashing. i could see no damage but did see scales drop off after each episode of flashing. The one male who had been fighting with the Betta had clamped fins and one of his pectoral fins wasn't moving. But all three of the platies started intermittent flashing. The five gallon went through a few days of .25 ammonia, 1 nitrite and 20 nitrate. So I did daily 20 percent water changes with extra Prime and added Stress Coat. The five gallon is now cycled. Today I took the he/she/it platy back to the store. Total stocking now in the five gallon is two platies and three cories. The cories are fine, flying around the tank and having a blast. Over in the two gallon, the Betta is fine, none the worse for wear. The problem is the two platies. Both of them have clamped fins, and tonight the female flashed once or twice. The male flashed a few times. And the male is chasing the female. ALSO: My ph is very low, 6.4. I don't see any white spots on them. The female is staying close to the surface as I type, and the male is hiding out below. The carefree cories are oblivious. I appreciate any help, advice, suggestions, etc. that you have. I'm suspecting the pH, but not sure what to do about it. THANK YOU and thanks for reading through the long post!