Light timer & Air Pump Questions

[Becca]

Okay....so I have my orchidarium set up..woohoo! Now I have a few questions and cannot get a hold of the company who I bought it from to ask my questions so I thought I would ask for opinions/help on here!

1. My instructions said to have a triple plug (which came with the unit and not sure of exact names) plugged into my light timer....and running off of this will be my lights and air pump for the air stones. Why does this air pump need to be on a timer, aren't they built for running all the time for aquariums?
2. Do the air stones need to be covered with water or is it okay if they are partially submerged....there isn't enough depth to completly submerge them.
3. My timer is wacky....it is a Intermatic DT27. It has a setting to where it will come on and off according to your zone you live in...well that would be really cool if it would work....so far I have followed the instructions exactly and I can't get it to come on or off automatically. And to make things more complicated...it has a setting to choose days for sunset and sunup...but it is for ON at sunset and OFF at sunup...this is opposite of what I need! There is nothing in the instructions that mention how to change this and I don't think there is a way.....what a stupid timer! Must not be for plants? I am thinking of buying a different one, but I must act fast as I am leaving out of town for a week this Saturday and must have something in place by then! Please help!

TIA!