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.
Tank water heaters are heated by natural gas, propane gas, or electricity. There is no difference in the lifespan whether it is natural gas, propane or an electric water heater. Tankless water heaters have a longer lifespan of 20+ years. Water heater tanks are made out of a metal that has a sprayed-on glass lining. Inside the tank there is an anode rod, which is called the sacrificial rod in many instances.