It looks like it is working well. I agree that you need a check valve to
prevent backflow from the filter back to the pond. When you take it down
for cleaning, I would add a bulkhead fitting in the bottom to some plumbing
to drain the debris out of the bottom of the tub easily. The backwash would
only have to be done periodically, but would make the frequency of tearing
the whole system down much less.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html

"Herb" wrote in message
news:6eYHe.28736$MW5.2733@trnddc08...
RichToyBox wrote:

My bog filters were upflow gravel filters with plants as a veggie
filter.


http://pg.photos.yahoo.com/ph/herb_w....src=ph&store=
&prodid=&.done=http%3a//pg.photos.yahoo.com/ph/herb_watson/my_photos

If you get time to go look, I built what I guess is called an upflow
filter, based on bits and pieces of some things I found on the net. My
pond is a 165 gallon preformed, with lots of anacharis, a water lily,
and some hyacinth (which ain't doing that good). I bought a 50 gallon
pond "kit" from Wal-Mart, and modified it to make a bog filter. I put
the supplied pump into the main pond, plumbed it to a pvc manifold,
covered by a plasic mesh (the stuff they use in suspended ceilings for
flouresscent lights) to hold up a layer of lava rock, then pea gravel
that I planted several "Lowes" special plants in. To make it prettier,
my wife and I put a layer of aquarium gravel on top. The canna and one
of the other plants we put in are growing and spreading like weeds
across the bog filter. I occasionally add one of the bio (beneficial
bacteria) supplements. So far, I've never had even a trace of ammonia
or nitrite by sample. I don't have a lot of fish, four 5 to 6 inch
comets, and 4 plecostomus. I had string algae for a while, but even
that's gone now, and I can easily see the 24 inch deep bottom of my
pond. I'd appreciate hearing any comments you have that might make
things work better. One thing I know now, I need to add a check valve,
the way I have my filter plumbed in, if the power goes off, then the
water in the filter siphons back to the pond. If it went off a long
time, it could kill my plants, and destroy the beneficial bacteria.
ONe thing I'd love to do is put an air wand in the back of the pond to
make an air curtain. I have no idea what kind of air pump to buy that
could withstand the rigors of outdoor exposure. Any suggestions?
Sorry this is so long. Thanks.

Herb