Purchased this large piece of acrylic from Amazon to make my internal overflow box and weir.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Great product and couldn't find a better price. Cut well and glued nicely.
After it arrived I decided to change things up a bit on my sump. Rearranged so that I could have two filter socks and figured I would use left over pieces from this piece of acrylic to adjust the sump