Thanks ewest, I like the idea of a ballon valve. Where a source?
Alligator, not sure what you refer to as a "common drain pipe" but I put a drain pipe in my new pond. No stand pipe just a drain. Valve is on the outlet.
Stand pipes usually have a T at the bottom with a valve for draining in the horizontal (open to the pond) with the other horizontal end connected to the pipe thru the dam. The vertical opening of the T is where the stand pipe goes.
The benifit? As you can see the stand pipe will maintain water level in the pond & allow draining or lowering water level. The drain pipe can't be used for maintaining water level.
