I built my own "bio-filter" and it's worked fine all summer.
I read somewhere that one person used the plastic dish scrubbies (instead of
lava rock - b/c I'd also read that once lava rocks get "slimy", they should
be replaced - not so for the scrubbies!).......so I used that idea, got a
plastic file-folder holder at Wal-Mart (you can make it larger if your pond
is larger, but this was the perfect size for ours). Then I used another
suggestion I read and went to Lowe's and bought furnace filters - the blue
biodegradable kind you cut to fit - NOT the ones w/fiberglass in them. I
lined the "box" w/those, then stood scrubbies on end to fill the bottom, put
in my pump, then filled the rest of it w/the scrubbies - tightly - and
finally covered it w/another piece of the furnace filter - using two flat
rocks on top to hold it to the bottom. We also run a fountain out the top
off the pump. :-)

It really works well and we clean it on average once a week, but the pond
was filthy on the bottom to begin with and we've had a lot of rain this
summer, so after every rain, it needed cleaned. But the fish seem happy
(plants too).......and those scrubbies clean up *really* well and are
totally reusable!

But, to each his own - it works for us and it was really inexpensive.

Good luck w/whatever method you choose,
Nicole
--
Life is too important to be taken seriously. - Oscar Wilde
There is nothing like a dream to create the future. - Victor Hugo


"Paul Disdle" wrote in message
...

Does anyone have plans for a diy filter or a recommended site to find
some.

Paul