How long to grow back fins?

I have a betta that I treated for fin rot a couple months ago. I treated with Jungle Labs Fungus Eliminator, the powder. He had also been catching his fins on the decor I had in there and the filter, which I removed prior to treatment. His fins have not gotten any worse, and the ventral fins on the bottom have grown back pretty well. They were virtually nonexistent. However, his anal, caudal, and dorsal fins are almost the same as they were just after the treatment, perhaps a little better.

There is now nothing in the tank except for the gravel mixed with laterite and a few of those glass decorative bead things, the sponge filter, and the heater. The tank stays pretty much at 82 degrees.

Is this normal, or should I treat him again?

I had been doing 50-100% water changes weekly, as the tank is at work. I forgot to put in the tank specs. It's a 2.5g bowfront tank. I always do at least a 50% weekly, no matter what, but I guess I'll try to bump it up for a while to see if that makes a difference.

As far as medicating, I went by the instructions which was to do a 25% water change prior to dosing (I did something like 50%). It calls for 1tsp per 5 gallons, so I put in 1/2 tsp. It said "second dose may be added in 4 days after a 25% water change," so I did that but the wc may have been a little more than that, I'm not sure. I then let the second dose sit in the tank for another 4 or 5 days and did a 50-75% wc. Then I resumed my normal 50-75% weekly water changes.

Huh, I didn't know that either. The dorsal fin was only a little nub about a 1/4 inch long at the back, and that has gotten only a little better. It looks like it was sheared off at an angle with the back being longer. The front of it is now about a 1/4 inch and the back is about 1/2 an inch.

The caudal fin is perhaps a little tiny bit longer than it was just after treatment. It was about half the size it should be. The anal fin looked like it tore or melted in the middle of it so that the top of the tear was about a 1/4 or a little more away from the body. The front and back of that fin was nearly the size that it should be. So, it looked like there was a V shape chunk missing.

The pectoral fins were virtually untouched. They had a hint of a white edging that went away after treatment.

I guess I have to qualify my earlier post about the ventral fins. The one looks great and is pretty much grown all the way back. The other is not so nice. I think that is the one that was gone up to the body, but I'm not sure. That one is now almost a 1/2 inch long.

He swims quite well, but he likes to lay on those glass bead thingys, I think because they are smooth. I'm waiting for some anubias to come in the mail to add to his otherwise bare and boring tank. I'm thinking of tying them to a small piece of driftwood that I have that is attached to some slate. I'll have to check it for rough edges though. Otherwise, I might just go with a smooth rock I have.