Fish dieing one a day.

[Gordon Parks]

I have an established 40 gal aquarium that contained three small angels,
three cory's, 6 black skirt tetras and a three inch Pl*co. The tank had been
running with this load for around three months. I added three Zebra Danios
to the tank, and now I lose a fish every day. All fish are OK when I feed
them in the AM. All fish seem to be active and feeding but one will be dead
when I come home from work. No obvious trama (Nipped fins, bloat, loose or
missing scales) on the fish. The angels were the first to go. Now I am
losing my black skirts. I have tested my water myself and had the local
store check it as well and it is where it usually is. I would thing a water
problem would cause more than one fish a day to die or other symptoms. Ditto
for parasites or disease. Could the Zebras be harassing the other fish to
death? I have not witnessed them bothering the other fish ut they are the
only thing that has changed.

[Frank]

Gordon Parks wrote,
>I added three Zebra Danios
>to the tank, and now I lose a fish every day...

Does your tap water have chloramine in it and last water change mabe
you forgot to use a dechlorinator (?). If the gills of the dead fish
are brown instead of pink, the fish died from blood poisoning...

Most likely these fish brought something in. When fish start dying
without symptoms, it may very well be Saprolegnia - a parasitic fungus,
treated with both an anti-fungus and an anti-parasite. This parasitic
fungus invades gills and the fish slowly die of suffocation...

OR mabe gill parasites - gill flukes, dactylogyrus, gyrodactylus - the
fishs gills would be open all the time. By the time these parasites
kill, the fish should have red color at the base of their pectoral fins
(small fins on the sides of the fish). Then their gills become flared
(stay open) and they start gasping. You wouldn't have seen this
9gasping) if you were at work. Treatment - 1 to 10 dilution of hydrogen
peroxide - dip for 10 seconds, anymore will burn gills. OR you can
strip the fishs slime coat with a 30 sec. dip in 3% salt dip, and do a
three day treatment of QuickCure, followed by 2 or 3 days of 20% water
changes - the gills need the fresh water to prevent reinfestion...

Start feeding a medicated food twice a day for 10 days - it may be
bacterial............. Frank