If you need to save money two of the 150's would be preferrable to one 250 just because of price unless you found some super deal.

Plus light from two angles rather than one never hurt anything either.

Actually it's more about how tall of a plant a light can support, and how much floor area, but you can yield more on a 150 than you can on a 400 if you don't use the 400 right or can't keep the temperatures down, it all depends.

I just replaced my 250w halide with two of those $20 150's and I'm happy. I was going to use all three but didn't need it and it was just extra heat. I grow 2' plants max on a shelf in my closet at the moment, that's all. No big impressive grow here yet but that's all I needed. Flip clones and you will yield around 4-6oz per crop ea 60 days or so.

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