HELP! For the expert growers!

Hello everybody, this is my first post and my first time planting. I did some research already before posting this thread but couldn't find a good answer. So here is my grow-setup:
- Indoor closet (1,20 meters by 0,80 meters and 1,80 meters in height)
- Cfl growing ( 2x 105 watt, 3 x 85 watt and 1x 26 watt, all are 6500 K) all about 2/3 inches away from the plants
- 3 plants, all about 2/3 weeks old in 7 Liter pots (1,8 gallons)
- 1 small computer fan blowing on the plants and a bigger one in the top op the closet for getting the heat out
- The whole closet is covered with mylar
- I use BioHeaven 2ml/L and Bio-Grow 1ml/L eacht time I water (I only water when the top of the soil feels dry (1 time in 2 days usually))
- I use all-mix as soil for the plants
- I do low-stress training every 2 days but wash my hands really good with a anti-bacterial soap
Problem:
I have 3 plants, 1 looked really good, one is oke and the third one looks a bit strange. They were all doing pretty good but one day I thought I could put the plants in the sun (The sun is really hot here, live in the Caribbean) so I could work a bit more on my closet. After that I put the plants back in the closet so it can still have it's 20/4 light routine. After a day or two the bottom leaves of 2 plants become yellow and began to crumble while the top of the leaves looked fine! I want to know what caused this? Can this be over fertilization? Or is it because the plant got burned because I put them outside for a few hours? It can't be that the lamps are to hot because the top leaves closest to the lamps aren't burned at all. And also what do I need to do? Do I need to cut away the yellow leaves or let them there?

Thank you for helping, I really appreciate it!

I'm sorry btw if my English isn't that good, I live on a Dutch Island so I mostly speak Dutch here (probably that's why growing became my passion..)
Picture's coming in a second post!

There fine the bottom leaves will do that as long as the top is healthy your fine. Cheers

...and IMO just leave the yellowing fan leaves. They cost the plant a lot to make. Let the plant move all the nutes out of the fan leaves and when it wants to shed it it'll crumble.

That looks like a Ph problem still nothing to worry just check the Ph other then that there looking good.Cheers

btw, my ph is 5.5 here. What happens if the ph is to low? And I'm thinking of putting the plants outside when I want to flower, it's always 12 hour darkness here so that would be perfect for flowering right? Or will the quality be way less??

What can I do to make the ph higher? We don't have a lot of resources here so is there anything easy to get that doesn't harm the plant to higher/ lower the ph?? Our tap water is 5.5 here and I use this water for watering the plants. Thanks a lot for helping me, all the local grower weren't experienced enough or aren't taking high quality growing that serious so didn't have much help from them. Really thank you for helping me!!

You really shouldn’t change up your light ( talking from indoors to outdoors might mess the plants up) If the Ph is off it’ll be harder for the plant to absorb the nutes because the roots will start to get fucked. Nothing to freak out just add some Ph up your plants still look real good. 12/12 is great to flower 2500k and make sure there is no light leaks that will fuck your buds from growing nice and fat and could turn her to a herm. But to flower whats your node count?

The biggest one has 5 node's, then there's one with 3 node's and one with 2 node's. Thanks for the advice man, really appreciate it!!! I have two more small questions: the first one is that I have 3 plants, 2 look pretty good but one look pretty bad.
What can I do to make it grow better? Or shall I just kill it? And the second question is: Would it be smart to just make my best plant into a lot of clone's (because then I have a lot of clone's with good gene's right?) Instead of having one big good plant? (Ofcourse I need to make clone's when the plant is still in veg and check with one clown by putting this one in 12/12 if it's a female plant) Would it fuck up the quality? And will the yield be much bigger if I just make a lot of clone's and let those stand a few weeks in veg and then flower instead of leaving just the one good plant? What would you do? Oh and what do I need to buy to make the PH higher?

you can add baking soda to raise the ph. I am not sure of how much to add though, sorry.

Thanks man! Every suggestion helps! Any idea's on the other questions I asked??

If you run your lights at 18/6 when your plant hits say 10 nods you can begin with 12/12 and you can take some clones off your best female but the more you take off each plant could weaken its dna line i would just pull off 2 per plant and the yield from what ive done and heard is more light more buds and fatter ones too. go to your local hydro/plant store and get ph up and ph down about 10 bucks a bottle and whatever the directions are start with half of that. i would have those plants on 18 hours of light for another 4-5 weeks then see where that at. also remember when you go on 12/12 no light when its suppose to be dark complete darkness and have a quit fan running also. hope this helps cheers

Be careful switching between indoor and outdoor...you can easily bring a bug into your growroom who will have the perfect environment to thrive in. Before you know it you'll have an infestation. My advice...once something (anything: a shovel a pot a plant a watering can) goes outdoors - it stays outdoors.

Good Luck
YO

thanks a lot man!! You think I should top the plant or just leave it like this?

thats up to you if you feel thats what you want to do then yeah wait till at least 6 nodes make sure clippers are sanitary (how ever you spell it) and only 1 time some say 2 the most but you don’t want to take the chance of stressing. the less stress the better chance of female. keep them in doors and top one till you get the hang of it remember not to stress them out should look into picking up some books so you can get better understanding of it. But this is a good site for info

also only use nutes once a month get yourself 3 gal pots and only use half the nutes they say to use and wait till week 5 to start with nutes i’m sorry i didn’t see that last time but you could also be burning your plants with to many nutes

I use bio-bizz they say it's pure organic so someone said to me you cant over nute your plants with this brand. I use the product growth-schedule. The schedule is on the site: www.biobizz.nl. Check it out! It also has all the specifics from the products they sell. Till know I only use Bio-grow and Bio-heaven, I'm gonna use Bio-bloom and topmax as soon as I'm gonna start flowering my plants. Let me know what you think! Again man, thanks for all the help!

Never kill any plant. Learn from it. If it still is salvageable just cut back nutes, water evenly and adequately and you'll be rewarded. It's a good feeling bringing a plant back from the edge. If it isn't salvageable you can experiment with it. Try giving it too much of something and not enough of something else. Play. But learn. And you'll become a better gardener