The gate valve is inside the cabinet, but my sump will not overflow if the power cuts out, I've tested it many times. When the tank is running, there is only 6" of water in the sump. That rope you see is the leak sensor
Why is my return so low? Inexperience, it was my first time every drilling and plumbing.
The return pump is a sicce syncra 6.0. A 3.0 will work, but there none available when I needed it and I didnt want to wait so I took the 6.0, which runs at 35%.
I actually have 5 different nozzles that I bought, I couldn't decide which one to use so I decided to think about it, but now I've gotten used to the way it is. I'm a "leave good enough alone" type of guy.
A pic of my sump is below, there are no baffles, the space was just getting too tight, and I have big clumsy hands, so I decided to leave it open. I've got rock rubble in there, and a small powerhead to keep the flow through the rock rubble.