I feed the same tetra sticks and know exactly what you mean in saying they fall apart, The best way to get a gar to top feed is to offer it frozen silversides right at the surface, after a bit the fish recognizes that it's food comes from above.
Once trained at this they usually will take all foods offered at the surface quickly.
I'm not sure what species of gar you have or the size of the fish However any gar under the size of 10 inches should never be starved. Gar are designed to grow quickly and with out proper nutrition in the first year they tend to suffer from it.