Blue Cheese... some advice ???

Hi. I started my blue cheese grow 2 weeks ago (They have been veggin for 13days)

8 ladies
Canna coco soil and pebs
600w HPS
Wilma self watering system givin each girl approx 1 pint (500mil) of water twice a day (for now)
All ventilation / extraction / carbon filter set up perfect and running temp is approx 27 - 31 Celcius

My problem is some of the tips of the first leaves are starting to curl up/down and are turning yellow and light brown... i have read about over watering and underwatering but cant diagnose why they seem to be turning brown.

It doesnt look too serious at the moment but dont want it to get worse and this is ofcourse a vital stage for the future of them...

Any ideas what i might be doing wrong?

(I gave them just water (chlorine free) for the first week of veg - the start of the 2nd week i have added to correct amounts of first stage nutes to the tank)

All water PH levels are spot on. I havnt checked the PH of the soil yet.

Any help appreciated

Andy

Can you post some pic? Has all the water been chlorine free?

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"cant diagnose why they seem to be turning brown."

Could be nutrient burn - are the tips of the leaves turning brown or spots on the leaves? If nute burn then you'll have to flush with clear water. At 2 weeks it doesn't take much to burn them.

Have you used coco medium before?

As MP says, we'll need pics to give you a better idea.

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How far is the light from the plants?

Will get some pics taken this eve and post cheers chaps...

Can you post some pic? Has all the water been chlorine free?

Click to expand...

Yep totally chlorine free from the start.

Could be nutrient burn - are the tips of the leaves turning brown or spots on the leaves? If nute burn then you'll have to flush with clear water. At 2 weeks it doesn't take much to burn them.

Have you used coco medium before?

Click to expand...

No spots on the leaves but yeah the tips are turning brown

Never used Coco medium before.

How far is the light from the plants?

Click to expand...

Approx 2 and half foot from plants... maybe 3ft.