I have a MarineLand 20 gal tanks (led light: day & moon light, penguin bio wheel filter, heater and air stone) with sword tails, platys, mollies and plecos with live plants and decorations. I'll admit I didn't educate myself enough before getting the fish, just went with the petsmart available staffs advises. Had the tank set up for less than a month and put the fishes in bec the store water test strips report read ok to add fish. The mollies and Dino's are either sick or dead from that particular store. I think its stress bec I got them on their restock day. But anyway, I think I found a good community with great deal of knowledges about the questions I'm about to ask. So here goes... From reading a lot of forms here I think My molly have fin rot. Before that she was spinning in the tank and I was sure she was going to die the next day. She stopped spinning and I notice the film around her body so I moved her out of the thank and placed her in the 2 gal tank with the glass shrimps. I had the shrimps there bec I didn't want them to get eaten by this one occasionally balloon molly who nips and also thought she nip the sick molly too but I nver saw it. She's breathing and looking ok except the fin rot. Next morning, I check to see if she is still alive and she is PLUS I found 10 babies. She didn't even look pregnant. To make my long story short, I took out the babies to the 20 gal tank. I did 50% water change to the 2 gal tank she is in and 25% water change to the 20 gal. (ammonia was reading 0.5 and PH was 7.6 for 20 gal). I read mollies like that pH). I forgot to test her tank before I changed the water. Questions: 1) will water change alone treat her condition? See attached pic. $18 to buy the medicine and its for this only one fish that I got for free. (If I didn't care I wouldn't be here.) 2. My balloon molly who used to swims around the tank is now hiding and I'm not sure if it is pregnant? Cuz I found one baby in the 20 gal tank. I don't know if that was left by the white moly before I transfer her. I bought the breeder container for safe keeping the babies I wonder if I need to quarantine her with the baby so her babies don't get eaten?? I can't find her to take a good pic of her belly. Yes, I have 2 small plecos. My husband got the white one bec we didn't know they have the black one and when I went the evening to return the dead fishes I saw the black one and got it. Once my 40 gal tank is set up I will move one of them out. I also bought them the wafer to feed them. Jk, it say it's too big of a file to upload.