Most aphids are host specific so they'll die in no time without some food source. If you have other plants in there, they might migrate, but most of the time they don't adjust to a new food source once they've gotten used to it. They're easy to get rid of, and if you have any small geckos or lizards, they'll use them as food (dart frogs will eat them too).
The easiest way is to knock them off the plant. They won't be able to climb back up to the juicy tender parts, so they'll die. Either a paint brush or knock them off will do. If they were in a garden, you could use a strong jet of water to send them flying, but in an enclosure it won't work well and misting isn't usually forceful enough.
Another method is to lightly 'paint' them with rubbing alcohol to dry out the protective coating and they'll shrivel up in a matter of hours.