redtailed shark

Hi I was just wondering if a male Betta could live with a red tail shark? Also any recommendations for Betta food? He currently likes bloodworms and brine shrimp but will not take pallets. A little picture of Bow the Betta

Redtailed Sharks, from Meijer. They were rescues from someone, we paid $6 each for four of them, one died so far after half a year. My question is, would adding a small amount of salt to their tanks help them as well? I haven't added anything to it at all, and we have well water, not even...