BETTA EXPERTS! I need help on this.. pictures included?

Question

Okay, so I have a community tank of 5 female bettas. I decided to get 3 Platys, knowing that my bettas would be intimidated by their size and leave them alone. Well a few days later, one of the Platys tail was half short and had white stuff on it.. then he sadly passed away. A couple days later after his death, one of my bettas had white stuff all over her body.. it wasn't ich because they weren't little white specks.. this was more serious. She sadly, also died. I was getting ready to separate the fish from their aquarium (thinking the aquarium had a contagious fungal infection), when I noticed one of my other bettas looking sick. I immediately seperated all of them into their cups with new water. My newly sick betta has stuff coming off of her gills and she isn't eating. She is at the top of her cup and it looks like something is infecting her fins.. she has a little bit of white on it. As I was taking pictures, I noticed that she had a little white string on her front fins near her head. Now, I think she has parasites or something. I know this is a long questions but I really, really need good answers. Also, don't get mad at me for putting them in their cups, they aren't staying in there for long.

http://i49.photobucket.com/albums/f280/Horsiegrl144/IMGA0972.jpg

http://i49.photobucket.com/albums/f280/Horsiegrl144/IMGA0974.jpg

http://i49.photobucket.com/albums/f280/Horsiegrl144/IMGA0982.jpg

http://i49.photobucket.com/albums/f280/Horsiegrl144/IMGA0978.jpg

http://i49.photobucket.com/albums/f280/Horsiegrl144/IMGA0980.jpg

Answer 1

Your platies introduced a protozoan parasite called velvet disease to your tank.  The velvet parasite belongs to the oodinium family and is similar to ich.  In it's free swimming stage, it must find a host within 24 hours or it will die.  It also contains chlorophyll and must have light to reproduce.  Copper sulfate medications are the most effective but fish infected with velvet usually are dead within 24 hours and by the time you see the fish with symptoms it will be too late to save them.  Darken the tank, raise the water temperature to about 85 degrees, remove the fish to a hospital tank if you intend to treat them with copper sulfate.  After 10 days of the copper sulfate treatment, if any fish are still alive, they should be safe to return to your main tank.  By then, any remaining parasites should have died off and you can resume normal lighting and gradually bring the temperature back to normal.

Answer 2

hooo-boy...  And that just happened in a day or so? it looks bacterial to me, not quite the same pattern as fungus infection...  I would probably use methelyne blue treatment, though, because it seems to help with a lot of different things like parasites, fungal and other skin/surface diseases, and I've never had any luck with bacterial-only treatments like Maracyn.  

Answer 3

Your fish has fin or tail rot.  It was probably the platy that infected your betta.  Get the appropriate medicine for this type of disease at your LFS.