For example, my 120 with a sump runs a 300w heater, dc return pump ~50w, circulation pump 30w, lighting ~300w. 12 hours lights on time, say 3-4 hours of heater on time (run my house at 72f, tanks at 78f)
So with that prob around 7KW/day, being $1.10-$1.75 a day to run ish... Assuming my math is...