Building a custom sump

[jwblocal701]

I forgot what size tank I used
But I had glass just about 3/16 smaller than the inside dimensions of the tank
Then used 100% pure silicone to seal and hold them in place

Sent from my iPhone using Tapatalk

 

[laverda]

With a sump you have to figure it will run @ about 1/2 full in order to accommodate the extra water draining from the tank& pluming on a shut down.
With baffles the 1st chamber can be taller for the fuge.

You should be able to run the sump closer to 3/4 full depending on the plumbing in the tank. If designed properly you should not get that much drain down on powering off. RC has a calculator for this based on overflow height. If you return is below the overflow use the height of the return instead. Than add a 2 inches or more as a safety margin.
For my 300 gallons n tank my 90 gallon sump is 20" deep and the normal water level is a little over 5" from the top. With power out the water level goes to 3.25" from the top. So I still have 3" of reserve. I have both levels marked on a tape on ruler on the side of my sump.