Reading up, watching videos and preparing for my new mist king system. questions....
Where is the best placement of the water supply bucket
IME, the bottom of the tube coming out of the reservoir should be
at least 4-6" above the bottom of the tube going into the pump. I tried less, and got occasional intermittent vapor lock. You also want the recommended 12 inch length between reservoir and pump. IDK why this is, but it also made a difference in reliable operation.
where does the actual motor pump thingy go?
This is less sensitive, but someplace you can access it in case of problems. They can be pretty quiet (at least mine is) so you may need to be able to feel it for vibration to determine if it's running or not.
Should the nozzle be placed in the front and spray toward the back?
Optional, but consider where the spray is going. I have my nozzles aimed toward the back so any overspray hits the pvc back & side walls of the enclosure rather than spraying into the room.
MK and Bill Strand both recommended front of the cage toward the back, which also facilitates adjustments & servicing if required.
And lastly, how often should I program it to spray?
That's the $64 question. Every situation is different; some trial & error may be required.
Often enough to reach & maintain adequate average humidity levels—day & night. I use 2 min. cycles because in my enclosure, that's sufficient to give everything a pretty good soaking; anything longer would result in a lot of water just running off & down the drain.
During the day, it's recommended that the enclosure be allowed to dry out completely between mistings. That will depend on your ambient RH, foliage (more is better) and other variables.
Live foliage helps raise & maintain humidity.
At night, you generally want higher average humidity, so more often or if you can't get the RH high enough, you may have to supplement with a fogger.