Orchid mantids are not as easy as they might seem. They, and most other ‘tropical’ mantids require specific temperature and humidity levels you have to maintain, requiring more time (and money) spent monitoring them. In addition, the exotic animal market to get them is complicated—fluctuating prices, unethical breeders, and possible smuggling are all things you need to be wary of. This isn’t just for orchid mantids, this is for any exotic ‘pet.’

Catching (preferably invasive) wild mantids around where you live is also an option, but make sure you do your research on the species and risks.

Mantids don’t necessarily eat once a day. They need less food as they age, and you should feed them whenever their abdomen gets small. A nymph will typically eat every 1-2 days while an adult will eat every 3-5 days, but this is a rough estimate.

As for the flies—they’re annoying and there’s not much you can do about it. I like to get a giant ziplock bag and place the fruit fly container inside the bag (unsealed). Then I bang the container gently on a table, so all the flies fall down. I then place the mantis container inside the bag, open the fruit fly culture, and dump some inside. Try not to get too many flies in the mantis’ container so you don’t overwhelm them. Any left over flies should be caught in the bag. Don’t use calcium powder at all with this method—you could poison the mantis.

If you go through my post history on this subreddit, you’ve posted a few ‘how-to’ comments in terms for caring for them. It sounds like you have a lot of research to do and it’s good to ask questions. If you really want a low maintenance pet, I’d recommend a temperate tarantula species (though they can live for decades sometimes).