My sun cluster eats like it's going to the gas chamber...
The pumps MUST be off so you can actually hit the target without watching a mix of food get swept away. They'll engulf and ingest a particle of food quickly and reopen if they want to consume more. (or at least mine do)
I'm now targeting the sun, multiple zoas and a frogspawn (recently) and their reaction is very entertaining. The venus fly trap has nothing on them.
I've been using a mix of brine, cyclop-eeze, flake, (virtually anything I stir up into a small mix) to blow across the tenticles and they will grab it all up.
Do you have a suitable clean up crew to collect up the scraps that the tentacles don't grab? I have a bunch of various shrimp that will pull food from the tentacles at first, then will lay back and wait for scraps...
When the feeding tube goes in, my clowns will actually sit down-current, wait, and eat like kings.
Feeading time at the zoo has become quite entertaining........