1250 can use non submerged, i am doing that, only space needed is the diameter of the tubing. Better to use non submerged as it's space saving and reduces heat input into the water from the pump
haha, doesn't matter. it's kind of like our body, cannot be too clean, otherwise we become weaker. same as biological lifeforms in marine ecosystem.
too bad I cannot use nsw as it will cost me at least $300 per wc,