No UVs here. I went the high plant load, low fish and small fish load way
from the beginning. Even this year, with the fish way too many and too big
(after 8 years) for the ponds and time to thin down the herd the ponds did
not turn pea soup green, just slightly tinted. I think part of the problem
was getting WHyacinths in a month later than normal.

I've since thinned the herd by 2, but didn't do it soon enough, now have 2
more in a sick tank. I'm going to try this Tricide-Neo stuff on them.

In my Lilypond, no UV and no human made filter, only a small fish spitter.
Again high plant load, low fish load. Actually I start out the spring with
no fish and wait for the tree frogs to do their thing. Once their young'uns
are big enough I bring out a few of my fantails and let them do their
thing. Full sun and no pea soup in it either. I do have algae on the sides,
and had a big crop of string algae, but one big harvest and that took care
of the worst of it once the lilies started putting pads on the surface.

So it can be done, no pea soup, without UV. ~ jan

See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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