Gary wrote:
I have a 2500 gallon pond, cement with liner, and woke up the other morning
to find that half the water was gone! I found a small hairline crack along
the smaller waterfall - perhaps a foot long. The water flows over the
crack; the crack is not submerged. I patched it and everything seems fine.
Does this make sense that this was the problem? 1200 gallons down in 12
hours?

Amazingly it is possible. Small holes can cause drops in inches, whereas
your hole was a foot long.

Also, now that I am paranoid, I had this idea for how to stop the pump if
the water drops. I have a 1/5" intake tube that goes to the bottom of the
pond. If I put a T coupling on it a couple of feet from the bottom, if the
pond ever dropped lower than that would I not lose prime and suction -
hence, causing the pump to stop pumping the pond dry?

It would, and you'd burn out your pump. Better to get an automatic shut
off. www.aquaticeco.com type in *mercury float switch* if the URL below
doesn't get you the
http://www.aquaticeco.com/index.cfm/...11432/cid/2965

~ jan


See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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