I have a 1 acre 0pond that's pretty much bowl shaped 10 feet deep max.
I have a 0523 Gast 1/3 horsepower pump. 80 feet of weighted hose going to a platform with 2 or 3 diffusers. 9 inch fine bubble diffusers. Vertex makes a good diffuser with built in check valves so you don't have to worry about water coming back up your line.
Do some reading in the Air section on this forum a lot of great info there for sure!!!
Once you get ready to pull the trigger holler at Bill Cody he may be able to help you out with parts and all or know who you can contact for the correct parts! He knows his stuff!!! Or holler at esshup I'm sure he could help you out too.
RC