"Peter Smith" wrote in message
...
I believe I have a serious water quality problem, and it is causing some
of
my fish to die, 14 in the last few days: here is the problem:

I have a 3,500 gall pond, stocked with about 70 fish of varying sizes (3"
to
26"). Almost all the fish are huddled at the bottom of the pond in one
area,
and they are slowly dieing with a range of diseases.

I have checked the water quality and here are the results: PH 9.5, Ammonia
0, Nitrite 0, Nitrate 0, Temp 5C. I have a very good filtration system
running, which does a complete water change every 3 hours. Water is
crystal
clear. There is some algae bloom on the surface, which is unusual at this
time of year.

Now I believe that my problem is caused by the low temp coupled with the
high PH is causing some kind of ammonia poisoning even though the reading
is
low.

What do others think and if it is a PH problem, how to I reduce it?

My first thought is overstocking. When did you take your ammonia reading?
What time of day?

Your 9.5 sounds high as well.

What are the fish dieing of? What are the symptoms?


--
BV
Webporgmaster of iheartmypond.com
http://www.iheartmypond.com
I'll be leaning on the bus stop post.