It is definitely high pressure sodium for flower being that the preferred light spectrum for flower is around 2700K which is the redder range of the rainbow compared to the vegative state where the preferred spectrum is 6500K or the blue range which the metal halide provides, although the HPS works very well for both veg and flower. One thing you may want to try for thickening up your buds is some material placed around the lower area of the plants to provide some light reflection into the lower and inner areas of the plants, I personally use foamcore for this because it gives plentiful yet soft light reflection, decent insulating qualities, easy to cut, and is cheap at wallyworld. The 1000 watt would give the capability to produce thicker buds for sure, but as silentleprechaun says, they get very hot...besides 2 400watt or 2 600watt lamps will absolutely destroy a 1000watt in all respects like lumens, heat, amperage draw, etc. After changing to a 1000 watt or adding another 600 or 400, extra ventilation will be an absolute necessity.

JSG.
JeffersonStateGrower Reviewed by JeffersonStateGrower on . MH or HPS to flower with? Which one do you use when flowering or which one is better? Also, Im about to start my 4th grow soon but have never really being happy with the thickness of the buds using a 600w HPS. Would a 1000w improve the thickness of the buds? Rating: 5