I got one of these a month or so ago and am amazed by how much my plants love it. Getting into this HID class of lights allows for big veggies. Lettuce, herbs, and seedlings are okay with t5. This kit has a ton of bang for the buck (no affiliation). the MH bulb is for veg growth and the HPS is for more flowering/fruiting: http://www.amazon.com/Apollo-Horticulture-GLK400GW19-Digital-Dimmable/dp/B004YXDHX6

I've read that 400w of one of these will do a 4' x 4' of dense plant area

Here are some links for the product in the above comment for different countries:

Link: http://www.amazon.com/Apollo-Horticulture-GLK400GW19-Digital-Dimmable/dp/B004YXDHX6

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