I would try and offer seaweed select. there are three kinds, green, red, brown, i would try one quater sheet folded up not too small each day on a plastic clip and fishin line, take out at night after lights out. replace each day. most mail order outlets have it. nori is good if it is not processed for human consumption. it must have no additives. hope this helps. the information you got from the fish man was the green stuff I memtioned. maybe this post will give you some more ideas. good luck keep us posted.