Pump power vs. pipe diameter

I've recently bought a pump and biofilter for my pond. The pond is about
1400 imperial gallons and is heavily stocked with fish. I've positioned the
biofilter above the waterfall which is about 6ft above the water level and
about 10 metres away from the pond, the waterfall lip is about 18 inches
wide and is connected by a stream. I bought a Yamitsu 12000 solids handling
pump and a Green2Clean 24000 filter which, in theory should both be more
than adequate for this pond. Unfortunately when the pond was built they used
18mm internal diameter pipe to supply the waterfall from the pond. As a
result the flow at the waterfall with this pump and biofilter is not much
more than a trickle. I have run a 38mm pipe between to test if this makes a
difference and it is much more acceptable. However, the original pipe is
buried in the ground under the pond, stream, rockery and waterfall, and
changing it for wider pipe would be an absolutely mammoth task that I would
prefer to avoid at all costs.
My question is: would getting a more powerful pump fix this problem? I have
had differing advice at several pond stores. Some say that the more powerful
pumps produce massive volumes of water but not a lot of pressure so would
still struggle to force the water up that diameter pump. Although at one
store I was told that narrower pipe is better as it creates more pressure
than wider pipe.
I would very much appreciate your comments and advice.
Jay.

"Anon" wrote:

> I've recently bought a pump and biofilter for my pond. The pond is about
> 1400 imperial gallons and is heavily stocked with fish. I've positioned the
> biofilter above the waterfall which is about 6ft above the water level and
> about 10 metres away from the pond, the waterfall lip is about 18 inches
> wide and is connected by a stream. I bought a Yamitsu 12000 solids handling
> pump and a Green2Clean 24000 filter which, in theory should both be more
> than adequate for this pond. Unfortunately when the pond was built they used
> 18mm internal diameter pipe to supply the waterfall from the pond. As a
> result the flow at the waterfall with this pump and biofilter is not much
> more than a trickle. I have run a 38mm pipe between to test if this makes a
> difference and it is much more acceptable. However, the original pipe is
> buried in the ground under the pond, stream, rockery and waterfall, and
> changing it for wider pipe would be an absolutely mammoth task that I would
> prefer to avoid at all costs.
> My question is: would getting a more powerful pump fix this problem? I have
> had differing advice at several pond stores. Some say that the more powerful
> pumps produce massive volumes of water but not a lot of pressure so would
> still struggle to force the water up that diameter pump. Although at one
> store I was told that narrower pipe is better as it creates more pressure
> than wider pipe.
> I would very much appreciate your comments and advice.
> Jay.
>
A bigger pipe is ALWAYS better than a small one. Even if the pipe diameter
is greater than the output diameter of the pump this is preferred. A bigger
pump will produce more whoosh, but at this point I would say the law of
diminishing returns kicks in. You can only push so much water through a
small diameter.

Does your pipe have to be in the location it is now? Perhaps you can replace
the pipe in a different location? Just disconnect the old one and pretend it
never existed. Alternately, can you run an additional pump and pipe to make
up the difference?

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

On Tue, 19 Jun 2007 11:14:03 CST, "Anon" <> wrote:

>I've recently bought a pump and biofilter for my pond. The pond is about
>1400 imperial gallons and is heavily stocked with fish. I've positioned the
>biofilter above the waterfall which is about 6ft above the water level and
>about 10 metres away from the pond, the waterfall lip is about 18 inches
>wide and is connected by a stream. I bought a Yamitsu 12000 solids handling
>pump and a Green2Clean 24000 filter which, in theory should both be more
>than adequate for this pond. Unfortunately when the pond was built they used
>18mm internal diameter pipe to supply the waterfall from the pond. As a
>result the flow at the waterfall with this pump and biofilter is not much
>more than a trickle. I have run a 38mm pipe between to test if this makes a
>difference and it is much more acceptable. However, the original pipe is
>buried in the ground under the pond, stream, rockery and waterfall, and
>changing it for wider pipe would be an absolutely mammoth task that I would
>prefer to avoid at all costs.
>My question is: would getting a more powerful pump fix this problem? I have
>had differing advice at several pond stores. Some say that the more powerful
>pumps produce massive volumes of water but not a lot of pressure so would
>still struggle to force the water up that diameter pump. Although at one
>store I was told that narrower pipe is better as it creates more pressure
>than wider pipe.
>I would very much appreciate your comments and advice.
>Jay.

What SD Joe said, diameter of pipe decides the flow, regardless of force.

>Check this link. It is from the makers of Sequence pumps.
>http://www.mdminc.com/Friction_Loss_Chart.htm

My first set up was with a garden hose that I buried. I just cut it off
below ground and left the rest. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

Thank you for the replies. The friction loss chart was very interesting; I'm
not sure I totally understand it, but I get the general gist. To be honest,
this is exactly what I expected to hear but what I most dreaded. There is no
easy way to run a new pipe to the waterfall. Even the easiest route means
excavating about 20 feet of rockery that has been in place about 25 years
and a pathway that crosses the rockery.
Maybe I need to have a complete rethink of my strategy. I desperately need
to get a filter but perhaps I should get a pressurised filter that I can
site away from the pond and run the pipes under the lawn. I know that wouldn't
solve the waterfall problem but maybe I'll have to live with a reduced flow
until I get the inclination to redo the rockery. Another advantage to that
would be that I could switch the waterfall off at night. I have been worried
what the neighbours might say about the noise! What do you think?
Also, I would be interested to hear what diameter pipe people commonly use
for connecting pumps to waterfalls in a pond of my size (about 1400 imperial
gallons) or is it just a case of using the biggest they can find?
Thanks again.
Jay.
"~ jan" <> wrote in message
news:...
> On Tue, 19 Jun 2007 11:14:03 CST, "Anon" <> wrote:
>
>>I've recently bought a pump and biofilter for my pond. The pond is about
>>1400 imperial gallons and is heavily stocked with fish. I've positioned
>>the
>>biofilter above the waterfall which is about 6ft above the water level and
>>about 10 metres away from the pond, the waterfall lip is about 18 inches
>>wide and is connected by a stream. I bought a Yamitsu 12000 solids
>>handling
>>pump and a Green2Clean 24000 filter which, in theory should both be more
>>than adequate for this pond. Unfortunately when the pond was built they
>>used
>>18mm internal diameter pipe to supply the waterfall from the pond. As a
>>result the flow at the waterfall with this pump and biofilter is not much
>>more than a trickle. I have run a 38mm pipe between to test if this makes
>>a
>>difference and it is much more acceptable. However, the original pipe is
>>buried in the ground under the pond, stream, rockery and waterfall, and
>>changing it for wider pipe would be an absolutely mammoth task that I
>>would
>>prefer to avoid at all costs.
>>My question is: would getting a more powerful pump fix this problem? I
>>have
>>had differing advice at several pond stores. Some say that the more
>>powerful
>>pumps produce massive volumes of water but not a lot of pressure so would
>>still struggle to force the water up that diameter pump. Although at one
>>store I was told that narrower pipe is better as it creates more pressure
>>than wider pipe.
>>I would very much appreciate your comments and advice.
>>Jay.
>
> What SD Joe said, diameter of pipe decides the flow, regardless of force.
>
>>Check this link. It is from the makers of Sequence pumps.
>>http://www.mdminc.com/Friction_Loss_Chart.htm
>
> My first set up was with a garden hose that I buried. I just cut it off
> below ground and left the rest. ~ jan
> ------------
> Zone 7a, SE Washington State
> Ponds: www.jjspond.us
>

Anon wrote:

> Thank you for the replies. The friction loss chart was very interesting;
> I'm not sure I totally understand it, but I get the general gist. To be
> honest, this is exactly what I expected to hear but what I most dreaded.
> There is no easy way to run a new pipe to the waterfall. Even the easiest
> route means excavating about 20 feet of rockery that has been in place
> about 25 years and a pathway that crosses the rockery.

What they said...

I'd add that anybody who told you that you should use a smaller pipe
to "create more force" needs to be reported to your local Better Business
Bureau. They shouldn't be in this business, as they clearly don't have a
clue.

Now, as to fixing the problem - might it be possible to run the pipe
_inside_ the pond and right up the face of the waterfall? The morons who
built my waterfall (and _also_ shouldn't have been in the business) should
have done that, instead of making two holes in the liner to go outside the
pond and then back in, and increasing the total length of pipe.
--
derek
- Unless otherwise noted, I speak for myself, not rec.ponds.moderated
moderators.

On Wed, 20 Jun 2007 04:09:48 CST, "Anon" <> wrote:

>until I get the inclination to redo the rockery. Another advantage to that
>would be that I could switch the waterfall off at night. I have been worried
>what the neighbours might say about the noise! What do you think?

I'd ask them, most people like waterfall music. ;-) It's frogs croaking
they might get upset with.

>Also, I would be interested to hear what diameter pipe people commonly use
>for connecting pumps to waterfalls in a pond of my size (about 1400 imperial
>gallons) or is it just a case of using the biggest they can find?
>Thanks again.
>Jay.

Depends on the flow, but for your size pond which is close to mine, 1.5
inch - 3.81 centimeters is what we used.

I was surprised when DS was digging for the buried pipe we put on the lily
pond, 1.5" looks so BIG, when you're imagining the smaller irrigation size
pipe. Currently he's found the pipes and attached the big ball valve to the
outlet pipe coming from skimmer and bottom drain. Last night he was out
marking levels with the water level. So it is progressing slowly, since one
has to work around computer business, shopping for parts and the heat....
which thankfully hasn't been too bad.... yet. ~ jan
------------
Zone 7a, SE Washington State
Ponds: www.jjspond.us

Ok. I'm slowly coming to terms with the fact that I'm going to need to
dismantle the rockery and path, although the very thought makes me sweat. I
think I'll do it at the end of summer when the plants are dying off.
Jan, you are right about the 1.5" pipe looking huge. I foolishly thought
that I might be able to get away with laying it on the surface of the
rockery and teasing a few plants over it! Don't think so!
When I do take the rockery apart to bury this pipe is there anything else I
should do whilst I'm at it? I'd hate to do it and then have to do it again
at some later date.
Jay

"Anon" <> wrote in message
news:_...
> I've recently bought a pump and biofilter for my pond. The pond is about
> 1400 imperial gallons and is heavily stocked with fish. I've positioned
> the biofilter above the waterfall which is about 6ft above the water level
> and about 10 metres away from the pond, the waterfall lip is about 18
> inches wide and is connected by a stream. I bought a Yamitsu 12000 solids
> handling pump and a Green2Clean 24000 filter which, in theory should both
> be more than adequate for this pond. Unfortunately when the pond was built
> they used 18mm internal diameter pipe to supply the waterfall from the
> pond. As a result the flow at the waterfall with this pump and biofilter
> is not much more than a trickle. I have run a 38mm pipe between to test if
> this makes a difference and it is much more acceptable. However, the
> original pipe is buried in the ground under the pond, stream, rockery and
> waterfall, and changing it for wider pipe would be an absolutely mammoth
> task that I would prefer to avoid at all costs.
> My question is: would getting a more powerful pump fix this problem? I
> have had differing advice at several pond stores. Some say that the more
> powerful pumps produce massive volumes of water but not a lot of pressure
> so would still struggle to force the water up that diameter pump. Although
> at one store I was told that narrower pipe is better as it creates more
> pressure than wider pipe.
> I would very much appreciate your comments and advice.
> Jay.
>