I have never been able to keep shad alive. I've tried a lot of different things: continuous flow-through aeration, circular tanks, ice, oxygen tabs, live well additives etc. Nothing worked. You'd be better off putting your shad on ice and saving those cooler-live wells for bluegill or other baits.
Class of 2014, Oceanography, Chemistry
U.S. Army E5 ret, OIF 2004, OEF 2008