PH shock, filter/heater leaking current, temperature shock, ammonia/nitrite?
spike, not enuf dechlorinator.
you have any crazy weather?
clean any filters/big water change or change anything



"Koi-Lo" wrote in message
...

wrote in message
oups.com...
I had a nice stable 10 gallon tank with 10 fish- 5 tetras, a couple
barbs, zebra danios. The fish had live several years and the tank
looked good with regular siphoning of the bottom and water changes.

The trouble started when I bought a new tank. I started it up and a
week later bought some fish. To introduce them slowly into the new
tank, I put a few into the old tank for a couple of days.

Which exposed the fish you already had to any number of parasites and
diseases the new fish carried.

A couple of days later, all 5 neon tetras died overnight. over the next
couple of days, the rest of my fish died. Same thing in the new tank
which was mostly guppies.

All new fish should be QUARANTINED for at last 14 days. If any sicken,
show parasites or die, stretch it out to 21 to 28 days.

Before the hardier ones died, they swam frantically, and often swam
upside down or vertically. When dead they sank to the bottom instead
of floating on the surface. Some of the dying were covered in white
"fuzz", but not all.

I check the pH and Nitrates, Nitrites and they were fine

Two questions: 1) Anyone know what might have caused this?
2) Any advice on how to clean the tank/ what to do before introducing
new fish?
Thanks

Since there is no way to know for sure what caused the white fuzz you
should sterilize the tank, the gravel.... everything! Then get a cheap
Quarantine tank........ see above. Never expose healthy fish to new
fish you buy.
--
Koi-Lo.... frugal ponding since 1995...
Aquariums since 1952
My Pond & Aquarium Pages:
http://tinyurl.com/9do58
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