Haether,

Here are some thoughts about cleaning your vf. Therat them with a grain of
salt as they apply to my pond and may not be relevant to yours.

The roots of the wh are great as mechanical filters and biosurface (bacteria
that you want). If they are filled with silt, they are working. Count on
them to be grabbing nutrients as well as filtering.

If your water is clear and the sediment seems to stay in the VF, leave it
alone til winter or next spring before the growth starts. Then suck out the
gunk.

Our vfs are cleaned once per year in the spring. The first filter pond has
over an inch of muck by then (5' kiddie pool). The next ponds have very
little muck. Conclusion, the first one does the trick. We have a bottom
drain in each vf, so draining in the spring is just opening the stopcock and
flushing by pouring some pondwater over the plants till the bottom is clean.

Are your wh growing well? Have they good roots? Is the water clear? If
so, leave it. It's doing fine.

Our wh grow at a huge rate in the Mississippi summer. We pull bushels of
them out. We also cut bushels of parrots feather and water celery. The
Irises are pretty, but don't grow as much (i.e. grab as much nutrient).

Good luck. Ours are up for view in the pondsite below.

home.bellsouth.net\p\pwp-jameshurley

Jim

--
____________________________________________
See our pond at: home.bellsouth.net\p\pwp-jameshurley
Ask me about Jog-A-Thon fundraiser (clears $120+ per child) at: jogathon.net

"Heather" wrote in message
...
Should the water hyacinth be removed from the filter from time to time and
the silt rinsed off the roots, then replaced? Or do I need to do
additional
filtering before the VF to get the silt caught first?

Thanks,

--
Heather
SW Ontario (Zone 5)