Solar Heater for Wading Pools

Have you ever had to fill a wading pool for your kids?  You can’t just use hose water, because it is too cold.  You have to add buckets of hot water from inside the house to make to water warm enough for the kids to swim in the pool.   This hauling buckets of hot water is a difficult mess.  You spill water on yourself and all over your kitchen floor.

The solution is a drop in solar heater that will cycle, filter and heat the water.  The pool will be cleaner and greener.  Now we just need to figure out how to build it and make it safe and cheap.  Should be easy right?