Anytime man. It was one of the best things I added to my canna line up. You mix some of the powder into plain ph'd water. Doesn't seem to mess with ph itself either fyi. Good for the roots big time. My root all was so big on my last one I could barely lift it to get it outside lol. Doesn't help it was in the basement don't know if this matters to you or not but I used to use LEDs after I tried MH and all I can say is my growth factors from the cmh exploded drastically. I got a 315 and a 630 and they cost me less to run than my other setups, produce more for me and cost me less on bills.