Rowly - Feeding rings can be flexable black poly pipe or rigid PVC w/ elbows and glue. 4" dia thin wall works good; 4'x4' or big as you want. feed ring 2ft x 4ft is almost too small to allow very many fish to feed within the area. Floats high in the water. As mentioned 1" PVC can also work. When I use 1" flexable poly pipe coupled with a connector and silicone glue and taped to help make it water tight, I add a wind baffle which is vinyl siding cut in 3-4" wide strips and attached to the inside of the ring; keeps the food in the ring better during splashing. 5-6 ft dia is about as tight as one can coil the 1.5 -2" dia black poly.
NOTE: Some types of fish cannot retain feed that is soft as mush because the small particles cannot be retained by the fish's gills and the mush feed passes out the mouth cavity through the gills. However some fish can get benefit from the soft mushy feed.
BC


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