pool heating

We gave up our gas heater just before winter, as beachfront wear and tear rusts them out regularly. After a winter of being unable to use my pool (just too cold this winter in central Florida), I am anxious to investigate alternatives for next winter that would wear better on the beach.
I came across this idea online: someone took a truck radiator, painted all the fins black, and put it where sun shines most of day. A 1/2 inch line was put on the discharge side of filter pump and run through the radiator. A faucet (I assume that means a valve) was put on the line to reduce or stop the flow. This method was used on a 20' x 40', 11' deep end pool in the midwestern US. They stated that it heated pool so well it often had to be shut off. Even on a a cold sunny day, like late September, it warmed the pool enough (82 to 84 degrees) to last for late night swim. The owner also had a gas heater, and stated he seldom had to use it as a booster to the home-made system.
It's much warmer here in central Florida (with lots of sun), and this seems a simple, elegant, and low cost way to warm up my pool in the winter. What do you think?

Lots of folks have success with DIY solar. Most thread I have read involve using black hose to pump the water through. Seems like a radiator should work too, but it's metal so as it corrodes it might add metals (and therefore stains) to your water.

Here's an example thread: http://www.poolforum.com/pf2/showthr...ar-pool-heater

A radiator is very small area compared to the volume of a pool so I don't think it would add much heat at all. The numbers don't add up. It is all about surface area with solar. Don't believe everything you read on the internet.

Yea.... I am buying a new heater this year... Wish there was a good alternative. Can live with 'em, can't live without 'em...