Rico in Spanish means rich in English just if your talking about money. If your talking about food rico means it's delicious, good, etc. Example, esto huele rico mean this smell good or  que Rica la comida means like delicious food in English. Puerto Rico means Rich Port in Spanish.
Tankless or demand-type water heaters heat water directly without the use of a storage tank. Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water. Solar water heaters use the sun's heat to provide hot water.
Control your water heater by the electric side, which is the toggle switch in the water heater compartment. As Dick said, ALWAYS make sure you have water in the hot water tank before turning on the electric side. No water in the tank will burn out the element in just seconds, I know from experience.