It must be Naughty Moose that uses a dish, it's not me.
I must admit that I've only once had problems with fish eating and that was bolivian rams which took a while to realise that what was going in the tank was food. After a while, these supposedly bottom feeders were eating from the surface. I even have a loach that feeds from the surface from time to time.
Something I have read to get fish feeding is to soak their food in garlic juice though I haven't tried it myself. Garlic juice is from cloves that you crush yourself or it is supposed to be available at supermarkets (again, no personal experience)
Frozen live food comes in a variety. I've seen bloodworm, daphnia, brine shrimp, black mosquito larvae, cyclops and mysis. None of my fish cared very much for black mosquito larvae and cyclops is very small - I use that in the tank with pygmy cories and Sundadanios both of which are very small - the shrimps in the same tank also eat it. If your fish are still young, they may be too small for bloodworm, though you can shave slivers off the cube which does chop the worms up. Mysis is like largish brine shrimps, I've only just tried that when I bought a mixed pack of 4 types.
Whichever you get you'll need to cut the cube up as they contain a huge amount of food for the size of the cube. Try a quarter the fist time, you can judge from that how much next time. Thaw it in some water before feeding it.
Someone has mentioned cubes of dried tubifex worms that you stick to the glass - my fish never cared for that either but you never know from tank to tank.
I have found that with food like flake, crushing it up small allows everyone to get some; the greedier fish can soon mop up whole flakes but it takes them a while to get round a lot of small bits.
Having said all that, the big tank had bloodworm this evening. The emperor tetras sat in a huddle where they knew the food was going in and demolished it all in a split second. Talk about a feeding frenzy, you'd thing they hadn't been fed for weeks. Luckily I also put in some cyclops left from the other tank for the small fish.