I am going to put 4 vho 48" bulbs and 2 no actinics on my tank. The question is how far should the bulbs be above the water level?

I would say about 4 inches. Just make sure you mount them in a way you can still get into the tank. What I would do is mount them in chains with hooks so you could raise them up to work on the tank and still have light to see what your doing.

Good idea dawg!!....and they said......... lol

make sure you use either plastic chains or coated chains so they don't rust.

I had put my vho's about 2-3" above the water. BUT, my chains rusted and they were a PITA to get out of the way, so now they're in the garage with the seaclone!