fin rot

[am]

aaaaaaaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhhhhhhhh !!!!!

I just noticed an outbreak of fin rot on my fire fish, gobie, and my clown.
There are a few other fish not affected. My water levels have been the
constant.
0 am
0 ni
0 to .25 nitrate
8.2 ph
79 deg
1.024 salinty
We did have a 4 hour black-out last week after I re-arranged the live rock
that stressed everyone. I have the skimmers on battery back-up now.

How can I treat everyone with out hurting the corals, and stars?

Thanks
Ron