Sick Damsel?

[lexi]

We have a new tank, been up 1 month (fish have been in it for two weeks)
Our domino damsel fish has gotten a white spot on it's caudel fin (just on
one side, on the very back tip of it's tail).
It looks like it is hanging off the tail a bit, but it just looks like a spot.
It is eating fine, sleeping fine, only strange behavior is that it likes to
stay in the current from the power head and just swims up against it (the
current) (although it does swim all over the tank too).
The three other damsel fish we have do not show any signs of this at all.
Thanks! We are two hours from a saltwater fish shop, and can't take it in
for diagnosis.

 

[frenchman]

Well... what is your setup? Do you have a UV light? What are your readings? Are you still cycling?
If I were you there are three things I would do or pay attention to:
- if you have a doubt, put the damsel into a quarantine tank (if you have one). You don't want him to contaminate other fishes or to become a net of parasites in your tank. Better to be safe than sorry.
- is the white spot growing? Does it look as if it's going to fall off? Then, you've got parasites
- observe the fish carefully. Does it scratch against a rock or anything in the tank, jerks from time to time or does strange movements?
- when it stops eating, that's basically it (it can take a couple of days or week).
BOTTOM LINE: if it's parasites, you don't want them to spread out in your tank and you need to take measures accordingly.