Hey Mike.

I've got an EasyPro system in my pond and it works very well. My pond is smaller than yours surface wise but I'm holding an acre foot of water and get a complete turnover every 3 hours. The system I bought is rated to 20 feet with a single diffuser (actually two 12" tubular membrane diffusers on a single supply line). I purchased it from a pond supply company after talking to their rep. Going into my second season with no issues...knock on wood.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!