I have about 800g system it was over a 1000g but sdg&e and a $750 electric bill made me rethink my system, i do about 120g a week water change using scripps water, which is the oceanography institute here in San Diego, where you can get sand filtered saltwater straight from the ocean for free..lucky us... i have a combo of a 200g in my fish room which is in the house, my intakes and returns are drilled thru the wall to the garage where i have a 250g sump filled with live rock..(no socks) a 6 foot bio ball chamber (old school) but i have a large fish load, a 4' ets skimmer and a 40g refuge, this is also attached to a 250g flat my frag tank and new stuff holding area (easy to get to), also connected to this system is two 40g breeder tanks for anenomes and odds and ends also use as a quarantee tanks...(when needed) i have approx 75 fish to feed my zoas.... since i do scripps water i only dose vitamin C every now and then..i add NO other chemicals to my tank...ph 8.4 cal 420 mag 1320 nit 0 nitrate 0 phos .25 never measure alk (no sps) i will post some picks...and if you have any questions dont hesitate to ask..........i love this addiction....thanks for looking...