Thanks for that link TheMetal1, going by whats been said on that thread I should be ideally aiming for 5000 lumens per sq ft But the thread doesnt make mention of what a 1000w MH will generally produce, does anyone know this?

anbesol, yeah i thought it might be overkill too, the bulb is *massive* but I guess its better to have too much than not enough. Plus, Its just lying around in a box somewhere so I might as well make use of it.