Hi,frozen blood worms are mostly water.You can get the freeze dried that are higher in protein content;much like the freeze dried black worms.You can also get black worms with beef heart.When fed raw BH/mix,more WC's and maintenance are required.You do not need to feed them BH to become nice large discus.BH is good when breeding and rearing young cause it is a cheap source of protein.A variety of food is best,like you're planning.