wrote in message
...
still deep water is going to go anaerobic. if there is light there will
be
significant algae. bacteria is everywhere. if everything except bacteria
were gone
we would see the outline of everything on earth.
drop in a couple good sized airstones and a pump and move that water and
it will
clear. Ingrid
snip

I concur fully. Sounds like the water is stagnant, so life has moved in.
Life you don't want, but life anyway. I'd add a few plants to Ingrid's
recipe as well.

BV.