lighting help please!!

OK i have asked this question before and cant seem to get any input....
I have a 4x8 table I that I have 36 square buckets with misting sprinklers. I have been using 2 1000 watt HPS lights. I am planning on buying new electronic ballast and am wondering can I get by with 2 600 watt lights? If not instead of buying 1000 watt should I get 3 600 watt lights?

Now lets say I am running two of these tables with a total of 4 1000 watt lights. There is 2 1/2 feet space between the two table, so maintenance can be done to both sides of each table. I have been trying to come up with a way to push both 4X4's together to make better use of the 1000 watt lights while being able to move it back apart to be able to do maintenance and care for that side of the table. Anyway thats another story, if I can work that out where it was 8X8 what would your suggestions be for lighting? One last hiccup is that table 1 is started week 1 and table 2 is started 3 to 4 weeks later. When table 1 is usually empty for week then cleaned and refilled. Then 3 to 4 weeks later next one is done and process repeats.

Here is a bit more information some may repeat itself.......
I think the finally size is going to be 8x8 if depending on what we work out of lighting. Currently we have 2 4x8 tables each with 2 1000 watt lights. There is about 2 feet between the tables and the finish about 4 weeks apart. We have thought of using casters to move tables in toward each other and apart to do maintaence, but height is an issue for us and if we cut the table height down the reservoirs won't have enough space. But, we are still trying to figure something out. Recently we added panels that hang from the ceiling with mylar that have really increased the fruits by 20% and the lower buds are all much bigger. I have heard and read on a few sites as well that the 600 watt HPS have the highest lumen per watt ratio of any HID bulb. The 600 watt HPS has 150 lumens per watt the 1000 watt is 140 lumens per watt. Which translates to 90,000 lumens for a 600 and 140,000 for the 1000 watt. Solar Max makes 95,000 lumen bulbs for 600 watt and 146,000 lumens for the 1000 watt. So if I were to run 3 600 watt lights it would be 285,000 watts and the 2 1000 watt lights would be 292,000. My thought was that with 3 600 watt lights it would be better coverage and almost the same lumens with 200 less watts. I will have to say the coverage with the mylar panels and 2000 watts over 4x8 isnt lacking awhole lot. Just figured since we are replacing ballasts with new digital ballasts if 600 was a better way to go then now was a good time. Though I personally think alot of the hype I heard was from a couple grow shops and at the time the 1000 watt digital ballasts werent on the market yet.
Anyhow thanks to all who responded and also to those that may.

 

Are you saying 2 1000's over the 4x4 or when i get the 2 tables together and put 2 1000's over the 8x8??

Thanks

 

Im currently running 2x1000's over 4x8, I am upgrading to electronic ballast. Should I stay with the 2x1000's over 4x8 or get 3x600 for the 4x8. The 1000 watt's will put out 292,00 lumens and the 600's will do 285,000. The 600 will putt off less heat, use less electric and will be 3 lights to cover the 4x8.