I use lava rock and love it but maybe not in the way that you are referring
to. I put my waterfall pump in a bucket (black 5 gallon) and then filled it
with lava rock. The water from the pump goes from my main pond into the
veggie tank (that overflows into the upper pond that then overflows into the
main pond. I never really clean the "filter" during the season. This
spring for other reasons I emptied the bucket out, rinse it out with pond
water, put the pump and rocks back in and start it up (I did rinse off the
really gunky rocks in pond water but not too much... that is where the good
stuff thrives I always thought). Really the only maintainence I do on my
pond is getting in to play (move rocks, plants, make asethic changes). I
hated the filter system that came with the kit that got me started and
almost gave up on ponding because of it. I had to rinse it at least twice a
week at the time to keep the water flowing (I didn't know about veggie
filters then). It was here that I heard about using lava rocks.

"K30a" wrote in message
...

Don't use lava rock.
The veggie filter will catch 'gunk' and the lava rock will be very hard to
clean.

My veggie filter is as simple as floating water hyacinths at the top of my
upflow mech/bio filter.
Things grow like crazy and I have to watch they don't plug the outlet.

Bonnie has a good veggie filter and pictures.
So does BV. Hope they catch this and post their
plans.


k30a
and the watergardening labradors
http://www.geocities.com/watergarden...dors/home.html