just remember your typical fiberglass bowfishing arrow can weigh up to 1500g setup full length. You can get them bare and cut to a shorter length and they also make carbonfiber ones also, there in the 600g weight range, still heavy and expensive, so for that heavy an arrow on a 20# genesis they wont be ideal, but you will stab some fish in shallower waters like said.
you may check out the Samick Sage series of takedown recurves, they are like $130 new and you could get little more poundage too, even 25-30# will be much better than 20# genesis, i have a 50# hoyt and i sometimes have problems so get as much as you can pull. but i do like a recurve for BFishin myself. Sage is a cheap but perfect for fishing rig, has all the holes to mount to in the riser also