I did the head pressure calculation of of my eheim 1250, pumping to my fuge, problem is only goes to 3/4 inch line, mine is 1/2. Well anyway says at 3/4 line, head pressure is 178gph through fuge. Is that enought flow. Keep in mind this refugium is on a stand pumping from sump draining back to sump. Refugium stand is the same height of my tank stand.