For more then 40 years the german company ROOS Freizeitanlagen GmbH in Altenstadt (near Frankfurt) is producing solar pool heating systems. Their system is called solar-rapid®. It is made of a special mixture of polypropylen, designed for regular pool or salt water use only!
It is extremely resistant to the UV radiation of the spanish sun. Our oldest installations on Costa Blanca have been done in 1992, and since then the ROOS collector is heating the pool of the happy owners without any significant problems!