Dropsy makes my skin crawl && Question about pinched fins

[Herbicide]

I have a new-ish split tail betta and for some reason his dorsal fin has become pinched. Also his top half of his tail is getting pinched too now.
He's in a 5.5 gallon tank with good water and I can't figure out what's wrong. I don't think it's velvet, and I don't know what to do.
Here's a picture that shows what his dorsal fin looks like.

When I first got him he looked like this: (the pic is from wikipedia but it looks a lot like him, but with a smaller tail lols)
http://upload.wikimedia.org/wikipedi...doubletail.jpg

[Herbicide]

Gosh, sorry those pics are so huge

[Oldfishlady]

How much and how often are your water changes and when was the last one? any additives used, what kind, what for and how much, water temp???
Any other symptoms, like flashing or rubbing, appetite, pooping okay
Is he the only fish in the tank and filtration and live plants?
Do you have any water pram number for ammonia, nitrite, nitrate, pH

He is a very pretty betta by the way......

[Herbicide]

I just moved him into the 5.5g because of the tail pinching. He used to be in a 1 gallon bowl. I do weekly water changes, about 30%
Right now i have just finished treating him with nox-ich, because I had thought it could be velvet. Didn't help.
Ammonia is a fat 0 (it's an established tank) and ph is upwards of 7.2 (I have hard tap water). The tank has a carbon filter (Whisper 10i) and no live plants. Currently no heater but I ordered a better one for my big tank, so it'll get the one that's on there now. It keeps the temp at about 78 degrees I think.
Oh and no other symptoms.

And thanks! I vowed to not buy any more from stores that treat them badly, but he just looked so pretty in that little cup.

[Oldfishlady]

I have found that my betta do better with twice weekly 50% water change with vacuuming with one of the changes in the 6g and less size tanks. Water quality can be a big issue for their fins/health and even with the 0ppm ammonia you have the DOC that can build up in non-planted tanks that can affect fins/health as well.

Also, being cold can cause them to clamp their fins, I would make a water change and get a heater to get the temp up to 80F at least, some betta seem to be more sensitive to temp than other, my young guys do fine in 76F but my middle age guys do better in 80F.

I know what you mean they are hard to resist....lol.....I have over a hundred but 99% of mine are home spawned......
Do you have nitrite, nitrate readings...btw

[Herbicide]

Nope, no nitrate/ite tests yet.
What is DOC? Should I put a plant in there?
And WOW! Over 100! That sounds like a lot of work!

[Herbicide]

In the 5.5 gal, his fins went back to normal :)