^^^ I completely agree with Bill. I had it in my small 8' dia pond when I had Mandarin and Wood Ducks there, and I had to put chicken wire around it or they'd eat it all. It helped utilize some of the nutrients that they pooped in the water. I'd take 3/4 of it out, and it'd fill the cage again in a month. Remove it for compost/fertilizer and repeat the process.

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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).