"rescue" betta fin-rot -- is it too late?

We have been tasked with taking care of my son's classroom fish over the summer.

When I went to pick them up yesterday, there was a new fish in the tank I hadn't seen before... an extremely emaciated, sad-looking Betta.

He was with 4 Harleys and a sailfin pleco in an unheated 20 long. The teacher had assured me that these fish had been healthy all year, and I'd planned to integrate them into my planted 46 bowfront.

I quickly decided this guy needed his own home, though, and pulled a 5 gallon out of the garage. I have a Whisper internal filter and 25W heater (set to 77). I used water from the 46 gallon to fill this tank and drip acclimated the Betta.

I haven't had a Betta for about 10 years. Is it too late to save him? What should I do? I have 1 tsp of aquarium salt in the water, planning to do a small water change later and replace the salt removed and add an additional teaspoon. I also have a pellet food containing sulfadimethoxine and ormetorprim sulfa. Would it be worthwhile to soak these pellets in the garlic and see if he'll take them? I don't have any water-borne antibiotic medications at this time.

He is extremely lethargic and may be blind in one or both eyes. I tempted him to eat one bloodworm soaked in garlic water last night, and he took one more this morning. But I have to target feed him with a medicine dropper -- he needs to be coaxed to eat.

Sorry about the ill-placed water spot in the picture. His side fins are very frayed, as well, making it difficult for him to swim.

Thanks!

Possible Change In Diagnosis?

Thanks Em and Deborah, for your advice and words of support. I really hope he pulls through.

However, after observing my community tank tonight, I have changed his diagnosis from "fin rot" to "being eaten alive". In the classroom, he was living with 4 schooling fish and a pleco. I misidentified the schooling fish as Harleys -- they are actually Serpae Tetras. DOH!!!

At any rate, those 4 are in my community tank as of yesterday and tonight I noticed some tail chunks missing from a few of my cherry barbs. Well, I observed a while after lights out tonight and saw one of the tetras take two swipes at my Gold Gourami's tail!!! :mad2:

So, I'm thinking this is what happened to the Betta, and now I'm worried about my community fish. I may have to dig up yet another tank (or ask the teacher for hers) for these tetras.

The Betta is doing okay -- he seems a bit livelier today and took two bloodworms tonight.

1 week progress update

Thanks again, everyone, for your advice! @Somervell - No, I am definitely *not* going to give this Betta back to the teacher!! I have worked too hard to send him back to be eaten up again! Maybe she was trying for some Darwinian experiential learning, or something!! LOL

I'm posting a few pictures. The first is a little blurry, but it's the best shot I could get of the fin regeneration. He is getting stronger and putting on a little weight, as well, I think.

Thanks again!!!