Quick search on ebay.. lots of neat duck decoys, a few frog and turtles that would work. But then thought...maybe i can put a floating light in and at night perhaps bugs would come to the light and fish could take a snack from time to time. I found an expensive one for pools and spas about $70 but also found this inexpensive color changing waterproof one about 4" sphere with a handy place to tie the diffuser tether up to smile

http://www.ebay.com/itm/New-Outdoor-Sola...=item416a77b7ed