First grow. Closent CFL grow.

Hey guys im a first timer so i figured i would become a member so i could get some advice. I currently have 3 young plants (bagseed) in my closent. To light them i am using 4 23 watt 5000k bulbs and a 23 watt flourescent tube. Dont worry this setup is temporary and i will find something more sturdy to support my plants and my lights in the near future. I also have a fan on in the top of the closent pointing down towards the plants. Current growing conditions: 70-80 degrees, humidity 45%, not sure about the ph or how to read that? Also dealt with a bit of nute burn so one of them look very unhealthy. The other two look unnaffected by the overfeeding. They just look a little overwatered but i dont know. So tell me what you think

 

Just some plain scotts potting soil for now but i plan on transplznting into a store bought organic soil when the time comes. Everyone says to make your own but i just dont have the time or resources for that. I stopped using nutrients and have been flushing for the past week or so. I was watering a bout every 3 or 4 days when they were in the basement but now that the humidity is lower, only every 2-3 days.
This may some dumb questions but where can i buy a ph meter? And what exactly is runoff?

 

Thanks for the input man. I will look into getting some ffof when i transplant them. One more question, when i transplant, should it be into 5 gallon pots or should i work my way up to a 5 gallon?