AHHHHHHHHHHH lobster roaches! LOL. That seems to be all I've talked about (another thread) the last 2 days on here. I NEVER talked about roaches as frog food before then. Weird. I never fed roach nymphs to my frogs. Of the rather long list, I can say thats one. Huh.
I have no special way of doing FF larvae, cuz I've honestly never done it. I did the pinheads with my tricolors (which I sadly have none of at the moment, something I hope to rectify) and that was the easiest and safest way I knew.
What I've heard on the subject is having a wet medium that gets the larvae to crawl up the sides of the culture. I nice rubber spatula scraper will get them off the sides and where you want to go. As for the adults, you can put them in the fidge for a very few minutes (doesn't take much) to slow them down (don't know how much that will help), feed them all out, dump them into another container then dump them back in after you are done (funnels help a lot for this).
The stripes are not hundbandry, but variation in pattern of populations. There are two lines I've worked with (one santa isabel, one anthonyi/salvias) that showed the "broad line" variation of pattern. The adults collected from the wild might have just been the "pretty" ones that the broad stripe was thought to be, but genetics showed the more common variations in the offspring. I don't believe them to be mutts, its just a pattern variation seen in the wild.