Fin rot and swollen belly?

Question
Hi Amber!

I have two male bettas who are kept separately in the same tank.  I have a couple of problems.  First, about a month ago, I tried to liven up the tank by putting in some elodea, but after a couple of days, the water turned green and the plants rotted (I dont know why)so I had to clean the tank and take out the plants.  Since then one of my bettas has been loosing his tail.  Chunks of it are falling off and he has got big splits in his tail.  It's looking pretty ratty and broken and its slowly getting worse.  He hasnt got much tail left anymore.  Is this fin rot? Can it grow back?  Apart from this incident with the plants, the water is always kept clean (cleaned every 1 to 2 weeks max)and the temperature is usually around 25 degrees, heated with a lamp at night.  My other betta didnt seem affected at all until just this week.  Now his tail is also starting to split and tear at the ends (there are no sharp objects in the tank).  
Also, this second fish will sometimes have a swollen belly.  The area just behind his gills will inconsistantly bulge and swell.  It doesnt seem to happen after he has just been fed and it only happens to the one fish.  It will last for about 8 hrs and then go down and flare up again a couple of days later.  Does it have something to do with the food i'm feeding him?  Can tetra flakes go off or bad?
Also, they always seem hungry.  When i feed them, they attack the flakes quite violently when they eat them.  I feed them a small pinch every day.  

Thanks alot in advance! I try to do everything right for them but these problems seem to arise!

Jessica


Answer
Hello Jessica-

To answer your last question first (about your guys being voraciously hungry) this is perfectly normal. A healthy betta is a hungry little piglet. All the time. So, if your bettas always seem hungry, they're probably pretty healthy.

About the bloating: You should switch to pellets, as flakes cause bloating in some sensitive fish. When they are swallowed, the fish swallows a lot of air as well, which causes the stomach to swell.

About the tails: This sounds like a tough case of fin rot. You should add a dose of aquarium salt to the tank each time your replace the water, to kill off bacteria and promote healing. Also, adding a dose of Melafix daily will help regrow the tail fins. This stuff works miracles! (Remember, small splits and curls are natural changes, but losing large chunks is not.)

Hope this is helpful!
-Amber Worman