COCO COIR Yellowing/ Browning Leaf Tips

[shaggy96]

Hello everyone,

I am 13 days into my first grow, trying out Northern Lights Autoflowers. I am growing in a medium of coco coir and 30% pearlite in 3-gallon fabric pots. I have a 24x24x48 grow tent using a Mars Hydro TS-600 hung Approx 24'' from the top of the plant. The tent has been kept consistently at 75-80 degrees and 70-75% RH, I have a fan circulating indirect air as well. I have not started feeding in any way yet, only watering with Ph balanced water (5.8-6.2) when dry. The plants have been getting 24 hours of light a day until two days ago when I put them on an 18Hr on/ 6Hr off-cycle. About three days ago I noticed the tips of the leaves starting to turn yellow and have progressively turned brown and begun to dry out. I have tried remedying it by checking all fronts (over or under watering, light burn, heat stress, etc). The first thing that comes to mind is nutrient burn but I haven't started feeding yet ( I was planning on starting tomorrow which would be two weeks since germination). Not sure if it could be a deficiency? Attaching some photos of the plant as well as the setup, any help is greatly appreciated!

Thanks

 

[Tersky]

My guess would be light burn. Seedlings are very sensitive to light and led's are notorious for being too intense for seedlings. Taken from their website: https://www.mars-hydro.com/mars-tsw-600-led-full-spectrum-hydroponic-led-grow-light

3.Recommended Hanging Distance Above Plants

Seedling: 30'' Germination: 24''-30'' Veg: 18''-24'' Flower: 12''-18''

I think you should move it to 30 and see if it helps. Those leaf tips will never recover btw but if the new growth should be ok

 

[shaggy96]

Thanks, I'll move the light up and see how things go. Thanks for the response!