Sorry, I wish a 10 day treatment with antibiotics would rid
Rainbowfish of Mycobacteria marinum. If so, believe me, we would
have heard about it by now! I was only speculating that it might
reduce the total number of Mycobacteria in the tank, the ones that
could re-infect the fish. Its might control total numbers of
pathogen; it won't eradicate them.
I wouldn't put much stock in any antibiotics. Antibiotics won't kill
the bacteria that's already holed up in the fish's organs and
tissues. Mycobacteria marinum (like the Mycobacteria that cause lung
tuberculosis) hide from the immune system within the macrophages
themselves, plus they have a waxy coating that makes them very
resistant to all chemical treatments. That's why hobbyists that get
the M. marinum disease (still a relatively rare occurence) have to be
treated with powerful antibiotic combinations for many months.
One correction to yesterday's letter. The scientific reference for
M. marinum disease spreading from aquaculture fish to wild fish in
Red Sea was: Diamant A et al. 2000. Mycobacteriosis in wild
rabbitfish Siganus rivulatus associated with cage farmng in the Gulf
of Eilat, Red Sea. Diseases Aquatic Organ 39: 211-219.
Stress (from whatever factor) always increases the likelihood of
disease. The factors influenceing Mycobacteriosis (infections from
M. marinum) in Rainbowfish are:
1. Introduction of a virulent pathogen (e.g., M. marinum) into the
tank
2. Numbers of the pathogen
3. Stressed fish
4. Strength of the fish's immunune system
Rainbowfish (unlike guppies) haven't been in the hobby long enough to
develop (genitically speaking) much immunity to a powerful pathogen
like M. marinumn.
I started keeping Rainbowfish in 1987. Those first fish (in heavily
planted tank) went through two years with no filtration. They did
fine through hot summers and many months without water changes and 90
ppm nitrate levels (Hey, it was a dry summer and my well kept going
dry). The fish thrived and there were no deaths (except a couple
jumping out of tank).
It is only now since the apparent introduction of a virulent pathogen
(most likely M. marinum in April 2004) that all my lovely fish are
on "life support".
I hope that my sad experience will warn others to be very careful in
purchasing Rainbowfish.
Unless you're buying from a seller that can guarantee the fish don't
carry M. marinum, my advice would be to buy eggs.