Using both MH and HPS together

Starting my 4th week of Veg under a 400w MH. Girls are doing great.Wondering if it would do good or bad to put a 400w HPS along side the MH for the next 2 week before flowering under 2 HPS?

Sounds like good idea to me! Just keep an eye on them temps and air flow I personally just use a 400w duel spec bulb

i,ve had good results using both in flower, especally for sativa dom. ...peace

Nice, thanks

Dude, I've only ever grown with both spectrums full-term, and have only had phenominal results, everytime. The blue in the mh helps keep shorter internodal length and helps in resin production, due to the uv spec it puts off-plants create resin specifically to block uv, so YES, absolutely grow under both! I have a 400W mh and three 250W hps in my closet, and I get outstanding resin-laden nugs everytime! Grow on man! ;^)