You can feed mostly silkworms and crickets, but feed less, since silkworms are more fatty. Silkworms have smooth bodies and supplements stick to them less easily, so be diligent about ensuring you feed plenty of dusted crickets. The issue with feeding silkworms only or a disproportionately large amount, is that the hard exoskeletons of insects, such as roaches, are a crucial part of a chameleon's digestive health. You should plan on maybe 1/3 roaches, 1/3 crickets ( adult crickets have more "shell", which you'll need ), and 1/3 silkworms. You could incorporate superworms as a once weekly addition to your rotation. Why the need for one feeder?