I read on this site in another thread about thermal covers. I wonder if someone makes a roll out version that's like a pick-up truck bed cover that retracts. one that would be strong enough to cover and protect against attacks from birds and raccoons that would still be able to allow some natural sunlight through but would also hold in heat and still provide shade too? That way it could be opened for viewing but kept covered for those of us that can't build a cover for the pond. I live where heat is my biggest issue, and I need to keep a cover, 5 ft straight down walls I don't think are good enough protection here. Every single fish I have lost since I rebuilt my pond has been by a predator and I think I've taken some pretty seriuos precautions trying to keep that from happening.