Electric tankless water heaters can be purchased at a local home improvement store. Stores like Lowe's and Home Depot sell this type of water heater at reasonable prices.
Gas, oil,electric,solar and I have even seen Bio mass water heaters.
Micathermic heaters are newer space heaters. It is a balance of convection and reflective heat that when mounted on a wall will heat a room significantly faster then traditional heaters. There are electric so may or may not be more cost effective but if that is not the issue it seems to be a good product. Many online reviews are favorable which is a lot to be said in this day and age.
Tropical fish.
Solar panels and heaters are used. They trap sun's energy.
thermal heat
Fully evolved Axew or Dieno, your starter, a grass water or fire type opposite to your starter and Excadrill or Krokodille. Remember, these are recommendations not musts.
water heaters electric stoves toasters space heaters incandescent lights are resistive loads a/c and fans iceboxs and anything with a motor is inductive Type your answer here...
electric is good against water type
It depends on what type of water heater do you have. For a gas-heater, 75 gallons is considered large. For the electric heater, 120 gallons is considered large.
Alkaline water
lime water