Question about Recirculating drip system

hey guys. I got a question about building a 16, 3 gallon bucket recirculating drip system. I got me a 5'x5'x6.5' grow tent and a 1000 watt hps. I want to put the buckets in rows of 4, 1' apart from each other. I would like to have my reservoir outside my grow tent if possible.

I drilled a hole 7/8" at the very bottom of each bucket and im going to connect them all together with a hose so the water can then return back to the reservoir.

My question is, do I need to raise my 3 gallon buckets above the reservoir so the water can flow back into the rez using gravity, or can i just keep them on the floor? If i can keep them on the floor "same level as the reservoir" does the water pump create enough suction to pull the water back into the rez?

the reason why im asking is if i have to raise the 3 gallon buckets above the rez i will loose about 2 feet of growth height which i don't want.

example of a system i saw on youtube:

http://www.youtube.com/watch?v=D63rzjt31yE&feature=related

When I drain my RDWC system all the water finds it's way out of the system using only gravity. The buckets and the res are all on the floor. You could just put a brick or a piece of wood under your buckets, raising them a few inches. It doesn't take much. Water will find a way. If you want it to drain faster then you may need an additional pump in the brain bucket to send the water back.

Buckets and Res can be on the same level. Word of caution, having them 1 inch away from each other isn't going to allow you to grow very large plants. I can get away having them that close in veg but only for 2-3 weeks max. Then it is too crowded and I have to space them out. Here is what I can do with about the same floor space.

This is 19 days in separated 1". There is 9 there. It's too crowded.

first i want to say thank you for the replies. so ill just put them on top of a piece of wood.

my buckets wont be 1 inch apart, their going to be 1 foot, i think you misread 1' for 1". and yeah ima do it similar to yours BendBrewer.
my first time doing a drip system, i got 20 seeds of Aurora Indica from Nirvana. I read it's pretty potent shit.
I bought the full OPTIMUM Hydroponix line + PH up and Down.
2 6 inch fans, one for intake and other for out.
air scrubber with air cooled tube, 1000W MH/1000W HPS.
Im going to be setting up my equipment this weekend and start posting pics to keep you guys up to date on my progress in my first drip system. i've done a bubblier before and turned out not to bad for first time.
i just hope to god i dont get a power outage.

thanks again guys.