So here's where some crossover between the reef tank and fishing helps. Bait tanks can be much simpler than this - but when you've got a bunch of aquarium plumbing parts lying around, it's tough not to go overboard. The hinged top keeps the gulls out and the bait in.

SS eyebolts, elastic chord and clips on all 4 corners secure the tank into the area behind the kayak's seat. Saltwater weighs 8.5lbs a gallon so it's going on 35 pounds when full so a drain of some kind near the base to help empty the water is important.

The most important part? The non-return valve at the base of the pump intake. It won't hold prime without it. Put the intake and output through your scupper holes and your good to go. The small tupperware container fastened to the top contains switch wiring and the large aligator clips that run to the battery when not in use.

I found some of the ideas for this tank here .... Quietman's bait tank