A sump is not for increasing the system volume totally but more about moving the agitated water past the skimmer and keeping the oils and waste in suspension . If you want to increase volume then you need a refugium . Also how overflow from the main tank when pumps go off will you tank/sump hold the excess water ? 72 gallon tank will have about 6 to 8 gallons of overflow if it was reef ready. _________ Some of the world's greatest feats were accomplished by people not smart enough to know they were impossible (Doug Larson) |