I have a small tank I was using for frag tank that was plumbed to my main system that I'm no longer using due to upgrade of my main tank. 10g tank with overflow and dual 3/4" drains and single 3/4" return. Comes with gate valve for main drain. You can plumb on its own or to your main system. Dimensions of tank are roughly 18" wide x 10" deep x 14" tall. Built by Concept in Calgary. Built like a tank with 10mm glass. Black acrylic on back. $70. Used for 6 months only.
Pics:
https://imgur.com/gallery/3WlYdnj
Located in Burnaby near BCIT.