Greg,

Your comment plants a seed of insight for me. We have about 10 koi,
full grown and half a dozen goldfish. The main pond is 2900 gal and the
berm ponds another 1000. There is a significant amount of muck that
gets caught in the berm veggie filters. If they did not get it, the
pond would. It simply does not 'go away', tho it is easy to drain out
by opening the 2" bottom drains.

I wonder if successful 'rocking' depends on the filtering out of waste.

We have an open cement bottom in the main pond. The koi constantly stir
the muck and it goes down the drain and up into the veggie filters.
Only pine needles build up in the main pond...and they generally find
their way down to the drain area (an old septic tank with the pump 4"
off the bottom).

Jim

Greg Cooper wrote:
Hi Jim:

My pond is about 900 Gal and has a skimmer and pump at one end pumping
around into a Aquascape biofall planted across the tope with watercress.

Mostly I think there is little or no muck because it is efficiently
broken down biologically. This year, after two years I lifted all the
filter material out of the biofalls and drained all the water out. I
expected to find material had accumulated on the bottom but there was
surprisingly little.

Granted I have lots of plants around the margins and my nine fish are
not that big yet. I do add Lymozyme every week and a anaerobic
bacterial agent in the winter.
It also helps that little leaves get past the net and what do get
removed by the skimmer.

When I used the "muck mop" it was to remove a excess of soft feathery
algae that was growing across the bottom to a height of about 3" so I
could not really see the rocks anymore. I used the Muck mop to suck
most of the algae up. That seemed to establish a different equilibrium.

Cheers.


Phyllis and Jim Hurley wrote:

Greg,

Thanks for commenting. How big is your pond and how do you filter it?
I am interested that there is no muck on the bottom. Where does it
go? Was there muck when you did your muck mop?

Jim

Greg Cooper wrote:

I have for 4 years now. The sides are lined with river "cobbles"
roughly the size of a brick and the bottom is lined with a few larger
"boulders" for interest and all around with round stones ranging from
3" down to about 1". Nothing smaller. I think this is important as
it still permits movement of water through. On the bottom the layer
is about 2 -4" of stones.

I like the look, the fish seem to do well the water has never turned
green ever. The pond is netted over (Raccoon defense) but that also
keeps the leaves out. I have never had a problem with accumulations
under the stones and I have checked - I can excavate down to the
liner and it is *Clean* all except a nice slimy bacteria coating.

Occasionally I have had an excess of a kind of feathery algae on the
bottom but I build a "muck Mop" to suck it up. But I have only had
to do this twice in 4 years.

That is my experience.

Phyllis and Jim Hurley wrote:

Do we have any ponders who have a bunch of rocks on the bottom of
their ponds? Have any of them tried it 'bare bottomed'? They might
be able to comment on the relative difficulty of maintaining them.

We are really happy with the ease of mainiaing the bare bottom pond.

Jim

JGW wrote:

We're getting ready to build our new pond. The contractor wants to
line the walls and bottom with rocks, which he says will serve as a
great huge biofilter. I have read that it's impossible to keep the
pond clean with rocks on the bottom, and that they can trap hydrogen
sulfide gas.

What are your thoughts?

Thanks.

Joan
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