No mark I only have the 1/4hp with two diffusers. I ran the power out to the edge of the pond. The Boulder (purchased locally at a Hardware store for $80)didn't have any air vents so I went to Home Depot and bought a package of plastic circular soffit vents and painted them to match the rock. They cost about $5 for 10 of them. I only used 6, two on the top side and four on the bottom side. I used 2ft sections of rebar attached every 5 to 8 feet with zip ties to sink the tubing. It does work but like I said it is a pain to put them all on and then drag the hose where you want it. If you have a couple extra people helping it won't be to bad. The rebar can be purchased at Home Depot also. My pump is 115 volt but we did run #10 wire to the area in case I ever sink a well to top off the pond.

Its not how well you do something,
Its how well you look doing it!