Mixing spectrums

So I'm 2 weeks and a couple days into flower with unknown strain and I hear good reviews about mixing vegg lights with flower lights to inprove yeild so if I added my 400 Watt mh alongside my 400 Watt hps would it mess up is it a bad idea alltogether some input would be helpful thanks

Deff not a bad idea. Go for it.
People pay good money for dual arc bulbs which is basically the same principle.

I run my Hortilux "Dual Arc" bulbs along side my regular hps bulbs and have been getting nothing but good results.

Thanks for the response bell you really think out wont mess up anything because I'm already 2 weeks into flower

I don't see how it would hurt unless heat is an issue. You may be wasting some of the spectrum (not being absorbed by the plants), but hurting, no would be your answer.

Cool ill add it in there tomorrow! And as for heat my tent is in front of a window in my room and one of the zipper doors is infront ofthe window so if my tent gets too hot I can open the window for a cool breeze plus 1 240 cmf and 1 120 cmf cooling inlines to help with heat I'm also going to add a window into so I can Controll temps at all times