Hiya!
Just had the same problem myself with danios eating corys food. I switched from sinking pellets to sinking microgranules - cos the pellets were to large to eat in 1 go, so there was a lot of chewing and spitting out - ample time for raids from danios. As my corys are still young, the microgranules are great cos they get eaten in 1 go. I use tetra microgranules. I feed the danios at the same time - and i found that switching the brand of flake helped too. they like it more so are less likely to go raiding.
And yes, it only took them a couple of nights to work out that dark = dinner. so i'm sticking to all getting fed together. I also bypass the danios by putting the granules into a turkey baster pipette thing and delivering the granules to the bottom of the tank, or they'd just get snapped up on the way down.
I'm sure you'll find a way - it was really upsetting to start off with that the corys weren't getting food, but after a while they realised they had to eat quick!
love
minkymaid