I spot feed my acans and blasto's at least 1 time a week and get good growth from them, especially the acans.
The blasto's, i thaw a big chunk of frozen cyclo peeze in just a little tank water so it is pretty think . I turn off the pumps and feed them each a squirt with a small syringes.
My acans i do the same with but alternate between frozen cyclopeeze and PE mysid. I will thaw a chunk and give as many heads as i can 1 shrimp each.
The blasto's wont grab the mysid quick enough and my tangs steal them from them so i gave up trying to feed them anything but the frozen cyclopeeze.