Kind you put mh in late in flower???what will that do for you???How late???I have both. I used to have a lot of cool tubes . I hate then . im currently switching them out with flat glass hood like a raptor xxxl hood for sog. ok the only thing good about cool tubes I have found is they may cool better then flat glass. what I hate about them. the light does not flood evenly all over the plants . you hit your head on that metal and it hurts ! third it take a year and a month to change bulbs I put in mh bulbs in late in harvest . 4 routine cleaning the dust out of the inside again sucks takes for ever. my opinion the glass reflector is better . with 1000 watt or 600 watt flat glass wins . don't get me wrong the cool tube does work. another good thing about cool tubes . you can buy them of ebay for 60 dollars us and they are good for placing in the center of a tomato cage and placing plants around them and grow that way or you can also put a light on top to to get max yields . another bad thing about cool tubes I have found it is much harder to resell them then flat glass reflectors . I buy and sell this equipment daily . the cool tubes just sit in the garage ,