with one little guy I just turned off all pumps so anything i dropped in would fall pretty much straight down. it was a pain to collect the uneaten, but it was a small tank, so not that bad and witht he pumps off I could drop it into a nice open area. Once he grabbed those free fall pieces I never needed a feeding stick - which, obviously, is the ideal.
there are some purveryors who sell quite small silversides, maybe you have to search for them. Also, like V. lioness said there are runts to be found in most packages. Or else just keep teying as many foods as you can.
IF he is really small, mysis shrimp might be better to use than silversides. You can get live ones if necessary, and mix in thawed-out frozen ones to train them on to that if required.
It might not be feesible for you right now, but these days I have learned that anything that has to be trained onto food goes into a mostly bare holding tank until they learn - it is MUCh easier to experiment that way without polluting the main tank - disturbing other fishes, etc... In fact, right now I am working on training a stonefish, who is being less than cooperative to say the least, but it is easier this way.
Just one more consideration (i promise
![Stick out tongue :p :p](https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f61b.png)
) - zebras are a comparitively difficult species of lion to ween. Much more so than volitans, fuzzy dwarfs, and russell's. So take that into account too: your struggle will probably be longer than most.