I'm not sure there is any good way to avoid mites except to make sure you keep things clean/sanitized. If a mite infestation does occur (even with the best of upkeep), you may need to treat your entire flock.
Most bird mites are more like a dust bunny rather than a blood sucker. I treat my entire flock every six months. Mites can infest airsacs and suffocate a bird over time. Wipe down cages thoroughly and use a shop vac hose inside of hard to get areas. I also treat with SCATT once a year with one drop on the armpit skin as directed. I'd rather prevent than deal with a big problem down the line.
I never had a case of mites with Pepsi and sprite , but you have to clean, sanatize, keep your house clean , and take your birds for check ups ( I take my budgies every month ) to avoid seriouse infestations