Why are the majority of bottom drains that I see shaped like upside-down
bowls?

My intent was to install two such drains in my pond, but now I am thinking I
may have an idea for different design. I am thinking I'll take a 5 foot
section of PVC (or about however long my pond is), and slice slits into the
pipe. Each slit would be 3/4'' to 1'' in width and they'd be spaced about
1-2 inches apart. Then lay those flat in the pond, and hook that up with
T-fittings to my plumbing. Then I would have a 5 foot long bottom drain
running the length of the pond. Depending on how I dig the pond, I could
also optimize the bottom of the hole for such a design, slanting the whole
bottom in one direction towards the drain.

Any thoughts? Aside from it possible being very visible, what are the
downsides to this idea?

--
BenignVanilla
tibetanbeefgarden.com
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BV,

The dome top is to keep the water flowing along the bottom of the pond
rather than coming in straight down. That helps to sweep the debris to the
drain.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"BenignVanilla" wrote in
message ...
Why are the majority of bottom drains that I see shaped like upside-down
bowls?

My intent was to install two such drains in my pond, but now I am thinking
I
may have an idea for different design. I am thinking I'll take a 5 foot
section of PVC (or about however long my pond is), and slice slits into
the
pipe. Each slit would be 3/4'' to 1'' in width and they'd be spaced about
1-2 inches apart. Then lay those flat in the pond, and hook that up with
T-fittings to my plumbing. Then I would have a 5 foot long bottom drain
running the length of the pond. Depending on how I dig the pond, I could
also optimize the bottom of the hole for such a design, slanting the whole
bottom in one direction towards the drain.

Any thoughts? Aside from it possible being very visible, what are the
downsides to this idea?

--
BenignVanilla
tibetanbeefgarden.com
x-no-archive: yes

Remove MY SPLEEN to email me.

Each slit would be 3/4'' to 1'' in width and they'd be spaced about 1-2
inches apart.

Any fish that might find their way through openings that large? A nice long
pipe with slits like that would be a very tempting refuge for smaller fish.

Another thought: I'm no fluid engineer but I suspect 99% of the water going
into the drain would enter through the slit closest to the closed pipe that
takes the water away. You'll probably get no draw from the end of a 5' length
of pipe.

If you go ahead with this design, I strongly suggest you dig the pond so there
is a channel for the pipe to lie in, have the slits on the underside, and slope
the floor of the pond so all the gunk gravitates toward the pipe. Keep in mind
this would be difficult to clean should the slits become clogged with leaves or
some other stuff.

I'm very happy with my dome drain.

~ Gary

Uh, clogging? A big opening will not clog as easily, and can be unclogged
with a garden hose or by simply closing the valve before the settlement
tank, draining the tank, then opening the valve. The resultant "swooosh"
will clear the clog. However, if you wanted to do the slit pipe thing (which
is one form of a retro-fit bottom drain), you can use black pipe or paint
the PVC to blend in. Personally, I wouldn't go with slits.

Regarding why bottom drains are domed: if there was no cover, the water
would only be sucked from directly above in a tornado fashion. Your fish and
anything that came close would get sucked in. The object is to force the
water to come in from the sides, not from the top, thereby sucking the
"stuff" from the bottom of the pond to the drain. If the cover is too flat,
it restricts the water flow. Therefore, a dome allows a greater flow of
water. Something else you should consider while you're thinking of bottom
drains: get the ones with diffusers in them. The air serves several
purposes, including introducing extra oxygen into your pond and giving the
fish bubbles to play in. But the greatest benefit is this: the rising air
bubbles change the barometric pressure and forcibly sucks the waste to the
drain. Something ELSE to think about G!

Lee

"BenignVanilla" wrote in
message ...
Why are the majority of bottom drains that I see shaped like upside-down
bowls?

My intent was to install two such drains in my pond, but now I am thinking
I
may have an idea for different design. I am thinking I'll take a 5 foot
section of PVC (or about however long my pond is), and slice slits into
the
pipe. Each slit would be 3/4'' to 1'' in width and they'd be spaced about
1-2 inches apart. Then lay those flat in the pond, and hook that up with
T-fittings to my plumbing. Then I would have a 5 foot long bottom drain
running the length of the pond. Depending on how I dig the pond, I could
also optimize the bottom of the hole for such a design, slanting the whole
bottom in one direction towards the drain.

Any thoughts? Aside from it possible being very visible, what are the
downsides to this idea?

--
BenignVanilla
tibetanbeefgarden.com
x-no-archive: yes

Remove MY SPLEEN to email me.