Bill:

Would a design of a floating island with things hanging down be improved if the floating island was of sufficient diameter to keep the hanging substrate in complete shade 100% of the time, or would there still be sufficient sunlight to allow FA to grow?

It might be a non-issue in ponds that have sufficient numbers of Tilapia stocked.

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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).