Blood worm is a natural food for many fish. All fish love blood worm, I've never known a fish not to like them. I would actually be feeding pellets a couple of times a day, with blood worm as a supplement. With the pellets, feed much as they can eat in two or three minutes and then stop.
When I feed my fish bloodworm, I always defrost it so it all breaks up and all the fish are able to forage for it, I like them to do this as I believe it's more natural and gives them something to do rather just hanging around waiting to be fed.