Has anyone used pallets to create artificial shade over other submerged structures ?

I used 2 treated fence pickets to join 2 pallets, then used swimming pool noodle sections (long foam sticks) wedged between the top and bottom slats to make them float. I drilled 1" hole in top of each pallet, then drove 1/2" rebar through that hole and into pond bottom to keep it positioned over rock pile in about 6 ft of water.

My thought was this should keep fish around the rocks more often throughout the day instead of moving to deep water earlier in the day.

I also thought about putting single floating pallets in about 2 ft of water in diffent areas to provide small fish a place to gather.

Does anyone else have ideas for creating shade in the absence of trees ?

Thanks,

Darryl