An evaporator tray 100 for a sauna heater comprising: a support member 104 one or more elongate plate members 102 extending across the support member 104, in which said plate members 102 comprise a concave, V-shaped, or U-shaped cross-section, wherein use the plate members support rocks 204 and collect unevaporated water thereby protecting the sauna heater. The tray 100 may included two horizontally stagger layers extending across the support member 104.
