I vote No Rocks.

I do, however, have several large rocks to keep the bottom weighted
down.

Before I did so, a heavy rain would cause the liner to float up, then
when the rain quit the pond would be several inches low.

When cleaning the nasty sludge in the spring, gravel would make it
almost impossible.

my two cents worth, good luck.
Mike


On Tue, 02 Aug 2005 14:47:39 -0700, 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
___________________


Mike Patterson
Please remove the spamtrap to email me.
"I always wanted to be somebody...I should have been more specific..." - Lily Tomlin

"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.

Never have, but sure know a lot that have and removed them after 1 - 2
years. ~ jan


~Power to the Porg, Flow On!~

"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
___________________



I have rocks on the bottom of my pond. I think it just looks better (IMHO),
but they are large rocks - not gravel. I also have a bottom drain that seems
effective.


San Diego Joe
4,000 - 5,000 Gallons.
Koi, Goldfish, and RES named Colombo.

Mike Patterson wrote:

I vote No Rocks.

I do, however, have several large rocks to keep the bottom weighted
down.

Before I did so, a heavy rain would cause the liner to float up, then
when the rain quit the pond would be several inches low.

When cleaning the nasty sludge in the spring, gravel would make it
almost impossible.

While I also vote "no rocks", I think there might be something to the idea
that there's a difference between rocks and gravel. Gravel would be worse.
--
derek

I've been trying to think how to construct a rather large screen dome
to place over the BD to address this problem. ("Large" = reduced
suction per sq.in. = small critters (and fish) can escape more
easily); but screen grid still large enough to permit mulm to pass
thru.

Or perhaps concentric domes of decreasing grid sizes(?)

Unnecessary complexity.

It's a difficult question isn't it? -- trying to solve two intertwined
but mutually exclusive problems at the same time!

Do you think it's worth experimenting?

Sure. Why not?

I think that you might start with:

1. Perforated PVC sheet.
2. An ability to draw a circle and cut it cleanly.
3. A dome (to place your hot pvc over, to form it)
4. A heat gun.
5. Elbow grease, safety precautions, and common sense.

I think you'll do fine, and the fabrication won't be as hard as you
think. Here's what you're looking for; it's probably expensive, and
if you hunt locally you'll be able to get it for less:

http://www.usplastic.com/catalog/pro...uct%5Fid=10081

Also, since you are thinking of novel screening solutions, you may
find this interesting:

http://www.aquaticeco.com/index.cfm/.../8559/cid/2079

Note that it is ever so slightly flexible (firm but somewhat soft). Not perfectly
rigid. It may get slighty deformed in shipping (mind did), but is easily straightened
with heat application (such as slipping it over 4" PVC and putting it in the sun).

C//

Courageous wrote:


Do you think it's worth experimenting?

Sure. Why not?

I think that you might start with:

1. Perforated PVC sheet.

Oh? Thanks for that link - I've never seen this stuff but pre-perforated
PVC sheet would be really useful for a project I have in mind...

2. An ability to draw a circle and cut it cleanly.

Uh-oh! That leaves me out :-)
--
derek

On Thu, 04 Aug 2005 19:02:20 -0700, Courageous
wrote:


I've been trying to think how to construct a rather large screen dome
to place over the BD to address this problem. ("Large" = reduced
suction per sq.in. = small critters (and fish) can escape more
easily); but screen grid still large enough to permit mulm to pass
thru.

It's a difficult question isn't it? -- trying to solve two intertwined
but mutually exclusive problems at the same time!

Do you think it's worth experimenting?

Sure. Why not?

I think that you might start with:

1. Perforated PVC sheet.
2. An ability to draw a circle and cut it cleanly.
3. A dome (to place your hot pvc over, to form it)
4. A heat gun.
5. Elbow grease, safety precautions, and common sense.

I think you'll do fine, and the fabrication won't be as hard as you
think. Here's what you're looking for; it's probably expensive, and
if you hunt locally you'll be able to get it for less:

http://www.usplastic.com/catalog/pro...uct%5Fid=10081

Also, since you are thinking of novel screening solutions, you may
find this interesting:

http://www.aquaticeco.com/index.cfm/.../8559/cid/2079

Note that it is ever so slightly flexible (firm but somewhat soft). Not perfectly
rigid. It may get slighty deformed in shipping (mind did), but is easily straightened
with heat application (such as slipping it over 4" PVC and putting it in the sun).

Thanks C//,
In my mind's eye I have been looking for products like both of these!
And great ideas for fabrication!
David

I have had a pond lined with river cobble on the sides and pebbles on
the bottom running for 4 years now. It looks very natural and is well
planted with lilies and various marginal plants. THe fish do well the
water has never been green and I have checked the bottom next to the
liner and there is zero accumulated deposits. I do have a strong
water flow giving good cirulation. I am happy with it. I like the
natural appearance. One point though - we paid more for very
attractively coloured river rock. A waste of money - after some months
the rocks grow a nice covering of beneficial algae so dont spend money
on fancy rocks.

Others like their rockless ponds just as much I am sure.

Greg.
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
___________________

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
___________________

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
___________________

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
___________________

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
___________________

While its usually agreed on that rocks in the bottom of a loi or GF
pond is not a good idea, its strange that rocks in a sal****er setup
is good, and bio balls are not desireable in the filter, but its the
trend to remove bio balls and filter type mats and just put in more
live rock rubble in their place........I probably has to do with the
type of rocks normally used in SW setups as compared to what is used
in a fish pond........I wonder how long its going to be until LFS //
Pond Suppliers etc start selling "Live Rock" for koi ponds.

Ponders do basically the same thing but in a different environment
with lava rock and trickle towers that live rock in a SW setup does by
being totally submerged.......

==============================================
Put some color in your cheeks...garden naked!
"The original frugal ponder"
~~~~ }((((o ~~~~~~ }{{{{o ~~~~~~~ }(((((o

Hi Jim,

I had forgotten that your piping goes directly from the sump into the
veggie filters. IMHO, a vortex settlement, or even a static
settlement tank, with bottom a bottom drain, between the sump and the
veggie filters would help this problem immensely. Further, for me
anyway, I am designing in mechanical filtration (brushes, matala,
etc.), and then bio-conversion (fluidized kaldness), between the
vortex and the veggie filter/stream. JMO, FWIW, YMMV....

David

On Sun, 07 Aug 2005 07:22:57 -0500, Phyllis and Jim Hurley
wrote:

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

While its usually agreed on that rocks in the bottom of a loi or GF
pond is not a good idea, its strange that rocks in a sal****er setup
is good, and bio balls are not desireable in the filter, but its the
trend to remove bio balls and filter type mats and just put in more
live rock rubble in their place........I probably has to do with the
type of rocks normally used in SW setups as compared to what is used
in a fish pond........I wonder how long its going to be until LFS //
Pond Suppliers etc start selling "Live Rock" for koi ponds.

In sal****er, particularly reef tanks, nitrates are a problem. Nitrates
form particularly well with bio ball set ups, hence these are starting
to be not used in sal****er tanks.

As for the substrate, one thing about ponds is that they tend to have
lots of external stuff (example, leaves) getting into them. This creates
a maintenance issue.

One can have the same issue in an aquarium... but the bottom is smaller.


C//