WTB 4" bottom drain

[High Plains Reefer]

any pondophiles have a 4" bottom drain? I am at the point of deciding wether to go all in on my koi pond/water garden and am considering a bottom drain system I have a skimmer already just need a drain, TPR's and a liner (33' x 25') I figure volume at 4700g give or take (no waterfall yet)

 

[AGGJSW]

Why are you wanting such a big bottom drain? 4" is pretty darn big for that. Your pond will be just a little smaller than mine. I have a 2" bottom drain that works real good. I also have the skimmer which feeds my filter as well as two other drains closer to the bottom (those are 4" each, one is complety shut off the other is maybe 1/2 open). My bottom drain is in the deepest part of the pond. All are gravity fed. I use a 7,400 gph pump. 4"! Wow, you must be moving a lot of water really fast... Just curious