Hello, I have a rainbow guppy that i've had for a long time, today i noticed that he was very bloated and his tail had took a lot of damage. I don't know when or how this happened, i watch this tank a lot, it had to have happened last night or something. He's in the tank with two other guppys and one platy. They're all very friendly and have been together for many months so i doubt he was attacked, but idk how else this tail damage could have happened. For the record, i don't know if it's a he or a she, my first guess was that it was pregnant but i doubt it as i've had them for months and there has been no breeding before. About a week ago i introduced new plants, shrimp, and a pleco. I don't have any way to quarantine them so i was wondering if they brought in some disease and what i can do about this. All the other fish seem very healthy. I did used to have another platy that we had for a very long time but he died several weeks ago. But he was getting old and was just a petsmart fish. The tank is cycled and all the paramaters are steady. i keep them at about 76 degrees. Sorry if some of the pictures are flipped, they didn't transfer to my computer very well.