browning leaf tips on seedlings

i have 3 plants under 2 X 23 w cfl and 2 X 15 w fluro fixture.
they started out fine but a 3 days in i noticed that 2 of the plants where behind, they havent grown their 3rd set of leafs, i can see that they had started but they just turned yellow and shriveled up (look at attached pics)
my 3rd plant had started growing its 3rd set of leafs but the tips of those have tiny brown spots on them as well. the other 2 leafs have brownish dry spot working its way up from the tip of the leafs
im new to this and dont have a clue as to what it is, please give input and sugestions
check out the pics

over watering?
you using nutes? if so stop
were they dryed up at all?

i let back on the watering, i keep the ph around 6 but i likes to kreep towards 7 so i use phosphoric acid to bring it down.
im not using nutes (any recomendations on what nutes to get, im looking at flora nova grow and bloom)
the medium was never let to dry out

here is an update with 2 pics
my main plant continues to grow, slowly. but the browning/yellowing at the tips of the matured leafs is spreading, because the plant is small im wondering if i should cut the bad part out of the leaf or remove the entire leaf? (marked in red is the unidentified browning)
im still not using any nutes but would like some input on what i should get (as i said i was lookin at floranova grow and bloom.
my other 2 plants are in the same condition, a 3rd set of leafs tried to start but shrived and turned yellow as you can see in the second pic marked in red but the plants also have 2 small leafs starting up that are still grean and look healthy marked in green

c'mon guys, any help at all
the one plant that has a 3rd set of leafs coming out is growing slowly but there and 4 more little leafs on the way that seem to be coming along healthy, but slow. but the 2nd set of leafs on that plant (1st set of real leafs) still has the brown spots on its tips and it still seems to be spreading...
it could be bute defficiency maybe as i didnt use nutrients at all
ph between 5.5 and 6
rockwool in hydroton (im having trouble getting nutes for my system, sould i plant the rockwool cubes into soil instead??
please any sugestions or help

https://www.rollitup.org/marijuana-plant-problems/132382-deficency-nute-burn-diagnostic.html

http://images.google.com/imgres?imgurl=http://www.gardenscure.com/420/attachments/plant-nursery/209849d1186314471-nursery-troubleshooting-guide-nutrient_chart.gif&imgrefurl=http://www.gardenscure.com/420/nursery-reference/105126-nursery-troubleshooting-guide.html&h=335&w=600&sz=32&hl=en&start=21&um=1&usg=__F3KMhnmZITGTZH2eDhbOvR_DScE=&tbnid=IEsbmNB-iJNiPM:&tbnh=75&tbnw=135&prev=/images?q=tomato+leaf+chlorosis+picture&um=1&hl=en&sa=X

based on the picture guide and the ones iv seen before id say its either nitrogen deff potasium deff or zinc deff those are the 3 that seem to match my probs, zinc not as much
i have transfered my babies from the rockwool cubes in hydroton into potting soil
im running on a low budget so i used soil from an outside garden patch, it was a bit heavy and i didnt have any perlite so i mixed in some of the small hydroton pellets
ill upload more pics of them in new pots but for now what recomendations can you make as for nutrients

here are my 2 little ones in soil, the third one has died
they look ok, but its my first grow so i have no real clue
they seem to be growing but they are now a week or 6 days in with 22 hours light on, i think a bit small??
hope they pull thru

check out these updated pics
it seems to be growing, just slowly
how much should i water my plants and how often
the soil was damp when i did the transplanting but rite now about an inch and a half down its moist but not wet enuf for the soil to be sticky enuf to stay on my finger
should i b giving them nutes
since im using fluroescent lighting and i dont have that much light i kept adding an hour to my light schedual every other day and im up to 22 hours on 2 off, is this ok, should i leave on 24 hours...
sorry bout all the questions but im new to this and i guess im a bit over worried...

im heading out to get 2 26 watt 6500K cfl's this afternoon and im also going to be looking at fertilizers, what kind of fert should i get, what n-p-k am i looking for, i also saw some bonemeal 12-0-0 and bone/blood meal 7-7-0 and i hear a few people saying they where adding that to the soil
i could use some help here, i dont want to keep delaying or risk doing something thatl ruin my babies
ill post some pics once i get the lights back on em

here are the pics, i managed to get a real closeup in supermacro so you can see details, my concern is the faint yellowing and the reddish brown discoloration on the tips of the leafs, as well she doesnt seem to be growing

im guessing my plants where nute defficient and that they got some transplant shock but things seem to be a bit better, im uploading 2 pics of each of my 2 plants, it looks like the color is clearing up and that new, healthy leafs are coming up.
i still havent purchased any nutrients and i wanna do this ASAP.
PLEASE help me with picking some nutrients and give some feedback as im rele in the dark here

Dude, go to an indoor garden store and ask for some all in one for vegging. Get a root stimulator (NoT Vigoro from HD), or B1. Use everthing @ a 1/4-1/2 dosage and chill

Your seedlings dont look too bad. Check out the GrowFAQ section. That answered a lot of my questions. About the light schedule.... I tried 24hr continuous. They grow about the same as 18/6. I took them off 24 hr b/c of electric bill. You should do some research on nutrients. Some are organic some aren't. I'm doing an organic grow so im using fish fert, molasses and bat guano. Growing in mg soil with CFLs. It took me a couple of rounds of seedlings to get it right. Rockwool was giving me a problem so I switched to soil. No problems since. Good luck

thanks for the advice
my plants are looking better as time goes on
i wanted to know now that im at 22 hours light on 2 hours dark should i continue rite to 24hrs light??

hey guys, heres an update, got them under a new 96watt t5 HO fixture with 2 6500k and 2 3000k bulbs, also got myself some flora nova grow nutes (using @ 1/3 strength) couldnt choose between 1/2 and 1/4, lol
ill have some pics up l8r today
whats your recomendation on lighting, how long should i be leaving them on, curently 24 hrs

i know i should get some perlite but im on a bit of a budget now so i put a bunch of small expanded clay pellets in with the soil. they are 10 days now. there are no rocks at the bottom, just the hydroton pellets i mentioned, and yes, there are drainage holes in the bottom
btw the feed solution i give the plants is at about ph 6.5 and water coming out bottom of pot is ph 7.0 is that normal??

i was told ph is extremely important for nutrient absorption
here are pics of my 2 plants, they are looking ok but it seems i have 2 little yellow dots on one of my leaves on my 1st plant (was there b4 i started nutes)
as i mentioned b4 i have started nutes, have done 1 watering only @ 1/3 recomended srength, sould next wattering be with just ph'd water or nutes again? and if yes wat strenght?
i also have a pic of my growbox, you can see i have a fan and my light is about 4-5 inches away from my plants

anything, anyone
improvements, recomendations