Without a timed watering misting system, or large volume dripping systems, it is very difficult to consistantly hydrate the chams for the length of time per hand misting that would be required to trigger many Chams to drink. In addition to triggering the drinking, many Chams won't drink while you are present, so they may dehydrate in the presence of hand misted water. Not to mention missing hand mistings due to being gone.
2 Solutions
IMHO, drippers and/or misting systems are the best way to ensure your Chams get the H20 they need,
hand misting should only be an additional water source, not the primary. For several years I only hand misted, but my Chams paid the price in my first learning experience. Often once the sunken eyes are spotted, damage has been done that compromises the health of the animal. For $150.00, Marty's misting system protects my investment, and I would not operate without it.
If Drippers are your solution
Drippers need to run at LEAST 20-30 minutes or so, again, to ensure the Cham is triggered to drink. Ideally, the dripper should run LONGER, which will require (as in misting systems) that you manage excess water.
I would guess if you don't have water run-off, you may not be watering enough. There are many ailments caused by dehydration, but none I know of from too much water! Err on the side too much water, you will have greater success in raising healthy animals.
Hope this helps

Nick Barta