Keeping them at an even 80-85F degrees 24/7 will produce enough for your single chameleon. Spray them once at night (I usually spray 10-15 squeezes of the sprayer) for humidity and water, and feeding a varied diet full of protien will help.
Anything below 80 and they will produce drastically slow compared to their full potential, but you'll still get some breeding. If you don't want much breeding at all, keep them below 80F.
If you keep them 90-110F degrees, you'll have tons, and you could sell the extras off, as dubias are easy to sell because they're the best feeder roach out there. I usually sell 100 for 20-25$, you can also do trades for butterworms and silkworms. This helps you out, helps someone else out, and helps your chameleon out!
I would feed a baby as much as it will eat for a few days, and based on how much he DOES eat, you will know how much to offer (probably a 8-15 a day).
As your chameleon becomes an adult, you can feed bigger roaches in smaller amounts, 5-8 larger nymphs every two days is good (or 3-5 adult males), or I prefer feeding 3-5 a day spread out through morning, lunch, and early evening by 6pm (lights out around 9-10).
Feeder lizards (anoles, house geckos, viper geckos, pictus geckos, mourning geckos) are all GREAT feeders for your lizards. I think a big step in herpetoculture in the next decade will be having a few breeding colonies of these feeder lizards.
Don't use wild caught ones though, could have parasites and other nasties, but definitely worth getting a breeding group going for the occasional treat.
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blackbetty, as for the red eyes, I cup-feed mine (well, more like a long jello dish), and this works well for me. I'd bet you anything that when you clean your frog tank out, you're gonna find a bunch of roaches hangin around.
I used to just toss them in, then a few months went by and I cleaned the cage out, almost 90% of what I had fed in the last few months had been living beneath the substrate! Definitely bowl feed your frogs. They'll get used to it and hang out near the bowl in the early evening when lights go out, which makes it easier to keep tabs on them too.
