IMO You never want more than one per pot. Too many problems could rise having multiple per pot. Such as roots getting tangled and plants fighting for the nutes and so on. As for the lights, if you can only afford one i would go with the HPS instead of the MH. MH works great for veg and HPS works great for veg and flower IMO. Good luck and be sure to do alot of reading on here. There's all kinds of kick ass info out there.:thumbsup: