"Dick" wrote in message
...
If adjustment to tank environment makes old fish susceptable to new
fish disease, then shouldn't this also happen when I move my fish from
one tank to another such as to the quarantine tank? I have moved fish
that look poorly to my quarantine tank and the change helps them. I
assume the fish I keep in the quarantine tank to keep it cycled are
less crowded and less aggressive allowing the "new to the tank" fish
to relax and eat better. I had a runt clown loach that was looking
close to death recover and start eating when I moved him to the
quarantine tank. I keep him in the quarantine tank since he seems
happy there. I also move fish, for instance, if one male seems to be
picked on, fins nipped. I often move the weak fish to the quarantine
tank and move one fish from the quarantine tank to keep fish count
balanced.

I don't think your example is applicable (if I understand you correctly).
The risk is when isolated fish are exposed to pathogens. All your tanks
would probably have the same diseases (or lack off) unless you practiced
isolation procedures (a net and algae scrub for each tank, and never
moving things between them). All your tank's water parameters will also
probably be idential (pH, gH and kH) making tank transfers easy.

NetMax

Since each tank has been established on its own each environment will
be unique. I have never seen such moves detrimental, it almost always
resulted in the sick becoming well, with no problem for the home fish.

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