Although it stays fairly warm here in Florida for about ten months of the year, there are those cooler days when it's still bearable to be out poolside in a bikini, but then the pool is chilly (to our standards which is anything under 80 degrees). Instead of installing expensive (and energy wasting) pool heaters, grinning and bearing it with chattering teeth or just giving up altogether, try this inexpensive and ingenious idea to heat your pool — hula hoops!
The creative people at Make Magazine have come up with these helpful — and, dare I say, cute — "lilypad pool warmers" made from black plastic tarp (polyethylene film) that's been soldered to hula hoops. They float on the surface of the water and attract heat from the sun, thus heating the water in the pool in the process.