I’m running a Herbie on my 75 gallon tank with a 20 gallon aga excuse for a sump with about 15 gallons in it. My return pump is a Jeabo DC 5500 running at about 75% this gives me 38 times turnover is this too much to turnover to use the sump as a refugeium? Can I put a true union ball valve on the return line to reduce the flow through the sump or would this cause a back pressure problem with the dc pump?
Also I notice the water level in the overflow drops at the same rate as the water level in the sump due to evaporated water. Is this normal for the Herbie system?
Also I notice the water level in the overflow drops at the same rate as the water level in the sump due to evaporated water. Is this normal for the Herbie system?

