I put the sinking algae tablets in my tank, the mollies and apple snail eat them, but i put them in for the cory, but he/she doesnt often (if at all) go directly onto them, instead he/she eats the particles the mollies make when they eat it. Also he/she just eats the flake food that falls to the bottom.
The tables dont break up easily, and are designed to be long lasting (day or so) and break up slowly, so if your cory's are over the tables and suckin on them, they will be getting food, and it doesnt necessarly have to take chunks from it.