I love Travis & Adam, but I am going to be the great big disagreeable opinion here.....
First, on
lighting. I'd say that much light over a 10g tank is sufficient for most anything you'd REALLY want to put in there. Intensity is a LOT less of an issue when you are talking about a shallow tank, which you are. Even a clam at the bottom of the tank would only be about 10 inches from the light, or less. So I'd say that as far as LIGHTING is concerned, you'd be fine for clams, sps, etc.
Second,
tank size. Let me really quickly add this caveat - your biggest problem maintaining stable water parameters, etc, is going to be the tiny size of this tank. THAT might be the sole factor that would make more sensitive critters such as SPS and clams a bad idea. However, you can combat this with water changes.
Third,
water changes (etc). With a tank that small, I'd skip any form of supplementation of chemicals, dosing, etc. Just do a good 1/3 water change once per week. Yep, you heard me, a full third. Make the water up a day in advance. Put an air bubbler in it and a heater. Make it match up with your target tank on temp. Perhaps if you REALLY want to be careful, check pH and buffer accordingly to match the target tank (though this really isn't likely necessary). And then do the water change.
And make sure to use a good salt mix such as Reef Crystals or the Red Sea Pro stuff. That will keep calcium, alk, magnesium, and those so called mystery "trace" elements in perfectly fine ranges. I really recommend Reef Crystals for it's low cost and good composition.
Forth,
testing. Shock, you can probably skip it all together if you do the aforementioned water changes. Except you'll want to have them around to test occasionally and in case of any problems. And they are fun to have around because, well, testing is fun. Makes me feel like a chemist for a bit of time...
And definitely, the refractometer is a good choice.
Anyhow, that is as long as my attention span can last in one place.... Welcome to COMAS!!!! And good luck... And happy new year!!!!