I'm putting together a 250+ gallon pond and I need some advice on heating it. Preferably something cost effective and low profile. Any tips? Thanks in advance.
A couple of 300W Jagers should easily do the job, and even better if you wish to run them on a controller. As for cost-effective, its simple physics that it wil take X watts of electricity to heat 250g of water from Y degrees to your desired temp, regardless of the kind of heater you use. If you want efficiency then make sure your tank (and the room it is in) is well insulated.