I started in the hobby back in 1991 with a 30 gallon reef tank and had that until around 2001. Back then, things were simple! :) I took a break and got back into the hobby in 2013 and wow have things changed! we started out with a 40 gal, then a 75 lead to a 90 which lead us to our current tank of 265 gallons. Being handy, I built the sump myself which is located in our basement with the display on the main floor. One of the most important things I focused on was, ease of maintenance with lots of filtration and the system had to be dead silent! There's nothing worse than listening to the gurgling of a drain. Therefore , our system uses the popular Bean Animal system on the overflows.

DIY sump measuring 96" long x 24" wide and 24" tall.
Approx: 220 gal capacity with an operating volume of 175 gallons.
1st chamber = 2 x 7" filter socks on inlet.
2nd chamber = 80gals containing skimmer.
3rd chamber = cheato rolling chamber.
4th chamber = Deep Sand Bed.
5th chamber = return pump and heaters, approx 35gals.

Plumbing from tank to sump is 1.5" PVC.
Running an over sized skimmer that is rated for a 500 - 850 gal system.