ill Guppy

Question
Hi,
i am worried about my male guppy fish. He appears to have a curving spine at the end, a slightly torn tail fin and cannot swim very well. Whereas the other 2 guppies i have can swim well, have no tears in their tail and have a straight spine. I previously had 5 guppies, of which i only have 2 males left, these also died after appearing with these symptoms. I clean the tank thoroughly every week, adding de-chlorinator as i do not have a water pump ( i have been told this is fine for guppies) and i add a blue liquid for white spot, as i have a fancy goldfish in the tank which needed treatment. This has no previously affected the guppies. I am hoping there is some sort of treatment or nutrients i can give to help the fish?

Answer
Well... it could mean a few things. Do you use salt in your tank? If you do, try raising them without it for a little while and see if it helps. What is the hardness of your water? Guppies usually like harder water than other species. How long have you had them? Where did you buy them? Often times fish purchased in Pet Stores are older. The curved spine is also an indication of inbreeding as well as not being fed properly when young. Unfortunately the most alarming diseases associated with the curved spine is TB. The fin rot can be treated with a medicated water conditioner. I use Aquarium Pharmaceuticals Stress Coat with Aloe. I add it once a week and with ever water change as directed on the bottle. It will help heal the damaged fins :)