This is the pump assembly. Rube
Goldberg would love it. The strainer basket filters
out big chunks and you just pour water into it to prime the pump. The inlet to the basket
sits below the water level in the pump well under the dock. The intake tube is laying on
the ground. It is connected by a union/valve. The intake tube and most of the plumbing is
2" PVC. That is a hardware cloth screen around the tube to keep the fish and frogs
out. A 4" PVC tube that is just short of the top of the water can be substituted for
the screen to act as a skimmer. The outlet is just a union. The whole thing is bolted down
with a rubber vibration pad to a board That board is fastened in the pump well to other
boards with deck screws. This makes for easy winter removal or repair.
After running this unit for a season we converted to a more efficient (and
more costly) unit. it should pay back in 3 years.
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Skimmer in action. We slit lengthwise a
10" piece of 4" tubing and slid it into another 4" tube to make an
adjustable sleeve that keeps the edge just below the water surface. The 2" intake
tube sucks inside the 4" tube to skim the top of the pond. |
The lower sleeve of the skimmer tube had
a bolt inserted across the bottom and then an inch and a half of cement was poured into
the bottom to keep it submerged. The inner sleeve is adjusted just below the water line. A
few frogs get sucked into the skimmer basket from time to time along with the leaves. They
can hold their breath for a long time though because we've only lost a couple of them. |
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You can see
the intake union/valve better. The valve can be turned off when the strainer basket is
emptied so the water won't siphon into the pump well. The red valve on the left is the
control for the waterfall. The red valve on the right is for the filter/discharge line.
The dock is obviously hinged on both ends and a black plastic sheet is in-between the
decking and the tie boards to keep rain out. 4x4's were pushed down into mortared
cement blocks and then they had all the voids packed with cement. The framing is 2x6's
leveled and attached to the 4x4's. The bottom is also cemented. The liner is attached to a
2x6 board along the edge of the pond under the dock. |