Here is a diagram i made when i built my first sump I found it hard to find a detailed diagram to work from so during the process of researching many diy sumps and combining many different sketches along with many unsuccessful attempts, I drew this, and it works great.
Now that I have had this sump running for 6 months or so I have a few alterations myself. Mainly I would have (and soon will once I get the time for a quick rebuild) inserted an extra panel in the 'IN' section to allow the water to drop in through a sock, opposed to the water rising, also since building the sump I have added a water level sensor, oppose to the traditional float types I added a small diafram type that simply senses the pressure when the water level drops and shuts of the return pump, and then back on automatically once the water level is restored.
I also made a diy overflow box that also hid two powerheads, again it worked great.
Hope this is helpful!
Tom
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