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Thank you for your comments everyone! I bet the reason why the aggressive fish seemed infertile was because she never let any of the males get close enough to her. I have a feeling mine will be that way too. She is still not pregnant. The other fish don't even have to be near her and she chases and nips them.
The reason why I thought they had ich at first was because their pectoral (side) fins had what I thought was a white dot or two. But seems to have just become torn fins. I was treating them for 3 days for ich and I no longer see a white dot, but just tears. I wanted to rid the tank of ich before it got too bad, thats why I went ahead and treated. I also don't believe its ich because the aggressive female is the only one that still looks perfect. I have stopped treating for ich.
I do have a net breeder with frame and it is bigger than the plastic breeder with the v slot in it. I'll put the aggressive female in the net one. I will probably only leave her in it for a few days because I don't like how those things get full of poop and left over food. Hopefully, she will calm down by then. I don't want to add more fish yet because I don't want to throw off the tanks cycle and add too many fish too soon. But I had the thought that maybe if I did add a few more female guppies to the tank it may help.... I didn't get any swordtails or platies because in the past when I had fish, their fry never made it to adolesence becuase they were eaten up so fast but with only guppies, their fry would grow to adults. I wonder though, if adding different breeds of fish would help with the aggression.
As for the pregnant female, her mouth is all messed up looking which started the day she first started releasing fry. At first I thought maybe she tried to eat one of them and it was partially stuck in her mouth, but it hasn't changed and it actually looks like part of the top "lip" of her mouth is missing. She definitely did not look like that before she released the fry. Maybe the aggressive female nipped her there? It could be she is just deterioriating like you said.
As for water paramenters... I don't have specific numbers or anything, but I let the tank sit with the filter running for a week and a half before I added fish. I know this isn't enough time to let it cycle, but I added stress zyme which says it helps to further along the bacterial or biological cycle by adding it the first day, the seventh and the fourteenth days, and I added the water conditioners (of course) and a bit of ammonia neutralizer in the beginning. I also have live plants in there and added a little bit of plant fertilizer. These forums also talk about adding a little bit of food to the tank to help the cycle start, so that is what I did the day I first started the filter. Anyway, I suppose the tank has been running fully about 2.5 weeks now. The water is clear and always around 78-80 degrees. Per the instructions on the box of ich meds, I have done about a 10% water change on the second day of treatment.