yellowing leaves

hi guys, just started my 1st grow, sowed seeds on 7th feb, kept them under cfl's and a 100w halo, then on sat i put them under 600w HID dual spec, temps are fine, 75-85f, rH is constant 27-32% one plant started out smaller thn the other, bit limp, and has had yellowing leaves,(all over)-think i may have overwatered this 1 and the leaves are drooping towards soil and withered, i left it to dry out and re watered throughout this time( nearly 2wks) the other has been ok, then today had a look and its starting to droop also, but still alot greener thn the other, have the lights 20" above plants, just took a ph test and its either 7 or 6.5 s its just a basic solution tester.

any ideas wat cld be, just checked the temp n its at 29c hum at 25%..???

any help wld be grateful, as i dont want to either over/under water them. i have them in bio bizz all-mix, was told this has 3wks of nutes, n not to add any to seedlings...

humidity is kinda low. 40%-60% are good humidity levels. make sure your ventilating the grow space to bring in fresh co2 or have a co2 generator or homemade co2.

water your plants when the top 1" soil is dry. fertilize every other watering with soil.

if you send pics of the whole plant and then the affected areas rip'ers can help determine ur problem

uhavealighter? said:

if you send pics of the whole plant and then the affected areas rip'ers can help determine ur problem

Click to expand...

cant upload yet but just sat and done a few tests, with my cab/warddrobe grow, with the doors open temps are as
soil surface = 25.5c
plant top temp = 27c
rH = 25%

soil Ph 6.0
tap water ph 7.2

thinking ph too low, made up a very weak fert solution of bio grow t a ph of 6.5 will this help any

i know the temps rise when doors are closed but yet too test how high they go to which im doing right now, with a bowl of boiling water to test rh and temps.....