The pool cover is made of multi-layer light weight construction having a translucent top layer to permit sunlight to pass through an opaque bottom layer for absorbing sunlight passing through the transparent layer. In addition, a plurality of pockets are formed in the opaque layer having air encapsulated therein. When in use, the opaque layer becomes heated by sunlight thereby transferring heat by contact to the body of the water in the pool while also blocking light from the body of water to inhibit algae growth. The heated trapped air also serves to conduct heat to the body of water while also acting as a thermal insulation barrier during non-daylight hours. The pool cover may also be turned upside down in use. In other embodiment, all layers may be opaque.
A soft, flexible, solar pool heater for floating on water generally comprises independently inflatable outer ring and central portion. When chamber and cavity are inflated, the cavity is with the top and bottom planes of the ring. The ring can be inflated with water for holding the heater in a pool in winds. Holes through the central portion permit egress of air from under the central portion when the heater is placed on water. Valves for chamber and cavity are located near one edge such that the heater may be deflated by rolling from an edge opposite the valves. Magnets on the ring condition water and attach to similar floating heaters to form rafts.