Cecil, something I thought up. Single membrane will float to the surface with the Vertex bottom line tubing attached (tested it first) and I needed a winter diffuser. But, I didn't want to keep pulling it in and out every year. I also wanted open water in front of the feeder so I could feed all winter long. Mission accomplished. When air isn't running in it (i.e. summertime) it is laying on the bottom and not in the way of fishing. I used either 1/4" or 3/8" braided nylon rope to set the depth. If the pond is at full pool it's about 1/3 the total pond depth. If the water drops, then it's less, but there is less total depth in the pond at the same time. That was the easiest way that I could figure out how to regulate the depth of the diffuser in regards to total pond depth for the winter with minimal work on my part.


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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).