Beginner grow come look and give me advice

Ok here's the deal. this is my first real grow meaning with seeds that just weren't out of a bag. I purchased 10 northern light seeds and also 10 white widow seeds. This is what i've done so far. I germinated the seeds in 2 seperate wet paper towels for 24hrs then planted them in two different color pots so that I can keep track of what seeds are what. I put the NL seeds in green pots and the WW seeds in orange pots. I put 2 seeds in each pot. This was done at 10:30 pm on tuesday may 10th. I then took the pots and put them in the closet, which will be my grow space for the time being. For lighting i'm using 2 40watt plant lights in a 40inch shop fixture(see pictures). The plants are about 4 inches from the lights and i also have a temperature and humidity guage in there. The temperature stays right in between 80-85 degrees and its always on high humidity. The light schedule i've been using is 18 on and 6 off. I purchased a timer so that schedule is always followed. The plants are all watered once daily as well. Its been 8 days since i've planted now and all 12 seeds that i've planted have come up. They range in height of about 4 inches for the tallest plants and 2.25 inches for the smallest plant. I am still debating on whether to transfer the plants outside or not so some advice on that would be much appreciated. I do live in the country so neighbor's wouldn't be a problem and the weather for the most part would be hot enough for them. I know I should probably be using an hps light or something similar but frankly don't have the money for one and i"ve seen people grow well with just the lights that i've purchased but i'd like some input there as well. Also I do have a fan on low that you can see in the pictures. Here are the pictures of what they look like so far. Tell me how you think they are doing.

 

so I need to put each one in its own pot. I can do that. Do you think that if I got another light fixture like I have with 2 40 grow blubs in it that would be sufficient? Also what do you mean by stretching? what can I do to prevent it?

 

Ok so its been a few weeks and I've moved them into their own pots and such. I've also got double the light that i started with. I kept the best 3 and I will be keeping those inside. Here is a picture of them sitting by the window on a nice day. They are still on a 18/6 and their watered once a day. I will be moving them to bigger pots but I'm unsure as to when I should do it. What do you guys think? any advice to give me? By the way this is 3 weeks exactly into my grow. How do they look for their age?

 

any suggestions on what i should use for fertilizers? I just recently started using superthrive. How is that? what should I use?

 

I recently noticed that one of my 3 plants leaves are turning a little brown. I'm unsure as to why. I water them once a day and always water the soil as to not get the leaves wet. i'm still on a 18/6 lighting schedule and the 3 plants are lit with 5 48'' 40 watt plant grow lights. I know that an hps light would be better but can't afford it right now. I also saw a post on here a little while back about someone doing just what I'm doing not and having great success so I know its possible. my plants are growing great i'm just unsure as to why the one plants leaves are starting to turn a yellowish color. I'm attaching 3 pictures of the current setup and also the plant that i'm talking about in hopes of people helping me out. thanks.