This is my 3rd growing set indoors and I have a recurring problem that I hope someone out here can help me with. I am currently using a 4’ x 4’ x 6’ reflective tent, 2 LED lights, 4" duct fan and CO2 bags. I am planting this time in 1 cubic foot boxes with coco planting mix, ph has been about 6.4. This time I am using distilled bottled water too.
But my problem that keeps recurring is as follows, I get a smooth germination and good start to the plants but usually at about 3 weeks old I start to see leaf tips burnt and dry from the bottom of the plant! See photos, any suggestions on what I am doing wrong or to stop this problem?
Is your coco without nutrients? If so; your PH is way high. It should be around 5.5 to 5.8. Any nutrient regimen should be at low TDS levels like 1/4 strength.
There are ph down products out there. I’ve used citric acid for years to achieve the same result. It comes in granular form (like salt), is cheap and available at the grocery store. A little goes a long way so you’ll need to experiment (I use the tip end of a butter knife to measure). Also, @Myfriendis410 is on the money. You’ll want the ph of your nutrient mix adjusted to the lower end of the recommended ph range for use in coco coir (which is 5.8-6.1). I adjust to 5.7/5.8 then apply nutrients to my plants.