Rainman,
Is you pan 2' square and sitting on botom or do you have them 2' off bottom?
The erosion prevention make total sence.
Bill I see how protecting the sides could make a difference. Almost like inside a box.
Thanks,
Chad
My pans extended beyond the diffusers. In the pictures RC51 posted, our diffuser array was similar, but in his, erosion could EASILY begin, and probably has, under the outer edges of each diffuser that has nothing solid under them. If the base is too small, and/or diffusers too low, the water moving under the diffusers can pull up sediment, and the diffuser just digs a hole into the pond. In RC's setup, I doubt it dug any hole under his base, but can almost guarantee there is erosion on the edges.
My diffusers were 6" above the base, and the base plate extended about 6" beyond the diffuser edges. After I looked at the pan I'd used, it was actually 30" x 36"....also, my diffuser edges were under 1" from touching.
