Ok, now that I'm home and have reread the medication bottle... it's called BETTAFIX and the active ingredient is "Melaleuca". I didn't mention it in the previous post, but here along the Gulf Coast of Alabama, it's pretty warm. We keep our thermostat set between 77 an 79 degrees right now, so I don't think the problem is water temperature.

Personaly, I find Tetracycline to be THE best bacterial remedy on the market. It is also the messiest product on the market and annoying to extricate from the environs. But I choose life over aesthetics and convenience.

ok, betta fix is just diluted melafix (tee tree oil). It's NOT an antibiotic, though it does have antiseptic properties.

How do you know the water was clean, were you testing it for ammonia? The water can look very clear, but still be very toxic for the fish. How often are you changing the water, and how often were you changing it in the 2L tank?

Tetracycline used to work great, however in many areas it's almost useless because of resistant bacteria. I've also never found it useful for fin rot. (This can be due to location however, as there are different strains of the bacteria that cause fin rot). I've never found it messy if used in the tablet or powder form, but it is hard to remove from a cycled aquarium. An uncycled bowl shouldn't be a problem though.

I personally like Maracyn 2, but that's just what works for me.

Anyhow, back to the OP. The melafix may help keep the area of exposed fin clean (think of it a bit like iodine or neosporin)and it helps in rin-regrowth, but if you don't see improvement in 2 days, I'd go and get an actual antibiotic (Again, I personally have the best luck with Maracyn 2, which treats mostly gram-negative bacteria). With the antibiotics, you would usually dose daily w/o water changes to build up a level of the meds (just like for people). Don't add more salt if you're not doing water changes.

You also don't need to keep salt in his tank all the time. Just use it for treatment at the rate of 1tsp per gallon. Disolve the salt first in a little tank water, then add it to the tank.

After treatment is finished and he's all better, you may want to get an ammonia test kit (the liquid kits work best). Do a water change, then test daily until you get readings (on a 2 gallon bowl with regular feeding, this should take about 5-8 days). If you get readings on day 8, then you know you should do water changes on day 7, so as to never expose your fish to toxic ammonia.

By the way, are you using bottled or tap water? If using tap water, what conditioner do you use? I prefer Amquel + or Prime, both are highly concentrated so you won't run out as fast, and both help your water quality. Those are the only 2 brands I'll use.

Try the link below, there's a betta board there and lots of articles on bettas and on fin rot.

Here is a link that might be useful: petfish.net

[quote]Tetracycline used to work great, however in many areas it's almost useless because of resistant bacteria. I've also never found it useful for fin rot. (This can be due to location however, as there are different strains of the bacteria that cause fin rot). I've never found it messy if used in the tablet or powder form, but it is hard to remove from a cycled aquarium. An uncycled bowl shouldn't be a problem though. [/quote]

I used to work at a wholesaler and we used TC, along with a variety of other bacterial and parasitic meds, all the time. I have watched our overcrowded tank shipments bet started on bacterial infections and TC would put in check by the next day. We gave it one full day of doing its job and do water changes every day hence to get rid of it.

^
Which is exactly why I said in "many areas". Not ALL areas. You can try TC all you want where I live, and it won't do you a lick of good. Go a few hours away, and it's fine. It really all depends on what strains of bacteria you're dealing with. And, unless you're willing to pay to find that out or have your own lab in which to do so, it's all just an educated guess anyhow.

Another thing we were taught was that if the fish weren't responding to one med, try another. In other words, if TC wasn't solving the problem, try EM or Maricyn or Maricide or formaldehyde or Acriflavine or Sulfa or....

Unless one is putting things under a microscope, one has to take an educated guess. We were barely aware of gram negative and gram positive bacteria. TC did the best, better than Penicillin / derivatives and dyes. We tried combinations, like salt, EM & TC.