Ice serves as a benefit. Have u ever put ice on a bruise to numb it? Think about ith that way , ice will cool with flow of smoke from the hit and make it easier to inhale. were all made up of water so how could it hurt? it just cools down the smoke making it more enjoyable , if ur bong has a ice...
well MH is good for flowering because it gives off more blue/red spectrum , of course u can use HPS for both but will u get the best results? NO , use MH for Veg and HPS for flowering , the conversion buld is worth it, trust ..
yea u can ofcourse , but would u rather have one plant full of buds or a few grams of hash , if u wanna be grimey u could always make hash and sell the left over bud just depends on ur preference