The submersible type is quite efficient since it can be placed right in the inline aquarium heater water in any position that you would like. Hard water isn’t necessarily bad for you, but it might pose difficulties with the plumbing in your house. To begin with, the hot water generated is far hotter than necessary, thus a cold-water mixing valve ought to be installed to decrease the possibility of scalding. Just because the water starts out at the ideal temperature doesn’t signify that it is going to stay that manner. In winter, or any time the pond water is cool, a koi will come to be quite lethargic, eating less and consequently producing less waste.