Its not a waste not telling him to put hps lights underneath . Sides would be better thats my bad works for me really well have 3 150 hps lights ontop of my babies and then have 4 flos inbetween on sides of the plant but kinda underneath. Wish I could post dam pics so I could show you guys what my set up looks like. Been reading a ton of late and everything I have read said mixing the lights up is killer for the plants having mostly hps but putting alittle blue in there is ok to. He wanted to switch out of using hps just gave a idea to use both like I do I will try to get pics up in another area so everyone can see my set up wish you the best of luck with your grow sorry for any confusion. Peace