possible sick female betta

Question
Hey Craig---  I have a 12 gallon tank setup with 6 female bettas, which all get along great.  My oldest one (which isnt too old, ie had her 3 months or so) seemed to blow up like a balloon, and her scales seem spikey.  Shes hanging up by the surface.  All the others are normal.  I do feed them twice a day, and another one is alittle heavy, but nothing like her. The other heavy one is just a hog, and is very active.  The one that blew up like a balloon was always active...what happened?  Over feeding, or shes sick?

Answer
Sounds like she has Dropsy, this is a bacterial infection normally caused by poor water conditions along with high stress.  Most commercial medications don't work and rarely will a fish recover.  What you can try is the following, do a 25 percent water change, increase the aquarium temp to around 80F, add 1 tablespoon of aquarium salt per gallon of water, after 4 days do a 20 percent water change, in another 4 days do a 20 percent water change and start to reduce the temperature back down to around 78F, in 4 more days do another 20 percent water change and then go to standard weekly water changes of 15 percent.  Good luck.