Need to double check baffle height


Premium Member
How much drains out of an AGA 75 megaflow tank when the pumps shut down? Trying to use the calculators for volume but not sure if it drains 1, 2, or 3 inches of water.

I'm building a sump/fuge with a 30gal tank 36x12x16 and 11" baffles. With 4.5" of space above the running level I will have 8.4 gallons of extra capacity.

If the 75 drains 1.5" that's 5.6 gal and all is good, however if it drains 3" I'll have two gal of water on the floor.

Is 11" to high for the baffles?


Moving About
Premium Member
I run a 90g Megaflow with a 30g sump and it drains back about 2" in total when the tank is off. This is about 1" into the pump area and another 1" across the whole sump. Allow for a full system shut down with skimmers and etc releasing their water back to get a better idea of max height.
My baffles are 11.5" tall across the sump. I still have plenty of room to spare when all water has drained back.

Here is a pic when I first did it over a yr ago


New member
Consider the volumn of water in the overflow also unless you have glued your durso and return pipe in (not reccomended). To start with if this is a new setup, pull the drain durso out and put all equipment in your sump to take it's volumn up. fill the tank and allow it to flow down to the sump untill it is full. Now start the return pump with your durso installed and it will let you see how high to run the sump baffles.