I have six silver hatchetfish who will only eat food at the surface of the water, so I have an "elaborate system" of feeding bloodworms. First, I put the frozen cube of bloodworms into a papertowel and smash it with a hammer. Most of the cube goes into a little cup with tank water to melt, but some of the cube that is broken up into little fish-size pieces goes back into the freezer in the papertowel to remain frozen for a few minutes longer.
After the worms in the cup thaw, I pour off most of the water, then get the still-frozen worms out of the freezer. The thawed worms go into the tank and immediately begin sinking, and those get eaten by the black neons & von rio tetras. The still-frozen worms get sprinkled on top of the water--and because they're frozen, they float a little longer, and that gives the hatchets a chance to eat them.
Any left over worms get eaten by the albino cories.