You can use (4) 400 watt HID, (3) 600 watt HID, or (2) 1000 watt HID lights. Now based on your square meters (I converted to square footage for ease), you can grow up to 66 plants maximum with 2 sqft. minimum of space for each one. If I was you I would grow 20-22 plants with 6 sqft. of space for...