Betta with bacterial infection?

Question
Hello, this may seem rather dumb but we have a very sick betta we are very
attached to.  He is the only fish; he is in a large bowl.  We change the water
every 2 weeks or so or when the water level starts to come down because of
evaporation (he has gone longer than 2 weeks in the past but since he has
been sick we have pretty much been doing weekly water changes).  He
started off with some lethargy and decreased appetite, which progressed into
small grey-ish lesions that started on his back just behind his gills.  He
seemed to retain his color fairly well and his fins have never clamped down.

We did a course of BettaFix, which seemed to help for about a week or so.
He was doing much better overall and had a better appetite but was still not
100% and the lesions were still present, so we tried a course of tetracyline
and flagyl in his bowl, following directions exactly and correcting the dose for
the size of his bowl.  I also put in an appropriate amount of aquarium salt.

He seemed to be doing better, but the lesions never went away completely.
He was more active for a while and was eating better.  However, over the past
couple of days Sebastian (the fish) has been refusing food, his color on his
body is getting more pale, and there seem to be a few more lesions.  He also
is tachypnic and tends to hang out at the top of his bowl.  Sometimes he turns
and floats on his side for a little bit but rights himself when he is talked to
(never a good sign, I know!).  He is pretty lethargic interrupted by spurts of
nervous fluttering of his side fins and jerky "jetting" around the bowl.  He
can't quite seem to swim right.  With the first round of illness he did some of
this.

The only other thing is that we seem to have more algae (?I think that's what
it is....grass green spots on his bowl decorations that comes off easily) on the
bowl decorations.

Do you have any suggestions for us?  I changed his water again tonight, and
paid special attention to his bowl decorations and scrubbed them down well
with a small brush.  I added some more aquarium salt and BettaFix...I also
started another cycle of Tetracycline (no flagyl, just the antibiotic).  I am
wondering, though, if the good bacteria in his bowl was destroyed and
caused an overgrowth of the bad?

We would appreciate any help or guidance you have.  We love our fish, and he
has hung in there for a while now, but we understand that he may not get
better.  We don't want him to suffer, but we don't want to "put him out of his
misery" too soon either.  If you have recommendations about what to use (or
not use), or if you think that he is too ill to recover, we'd appreciate your
thoughts.  The only other thing I can think to try is a different kind of
antibiotic (I think our local store carries a different class of antibiotic as well; I
can't remember which one).

Thank you so much!"

Answer
Hi Kristi,
   The algae isn't a problem. It is a normal part of all aquatic ecosystems.  

   As for the lesions, it sounds to me like he is just getting old. When bettas get old they start to fall apart.  Basically, a betta has a live-fast, die-young kind of life, hence the bright colors, and once they pass their peak, they tend to just deteriorate.  Sadly, most bettas only live about a year or so, though some do occasionally live much longer.  

  You can try another antiobiotic but I suspect that it won't solve the problem.  If it gets to the point where you feel that he has a very low quality of life, then the most humane thing to do is to put him in a plastic bag in the freezer.  I know that is a very hard thing to do.  Sorry.

-- Ron
  rcoleman@cichlidresearch.com
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