I have 4 seedlings, and only one has these; I was afraid it could be a fungal infection so I cut off the affected part yesterday, but now the whole plant is affected. I think I may see one spot developing on another plant near it, but I'm not sure. Im growing in around 65% coco coir/25% perlite/ 10% worm castings and for some reason the pH had raised to around 8, causing the leaves to be a line green color, so I saturated the (5 gallon) air pots with around 10 gallons of water at a pH of 5.5 til the runoff was around 6-6.5. This has all started since watering. I feel like the chances of it being a fungal infection are lower since I used mycorrhizae and mixed work castings in. Is it likely this is a symptom of overwatering? If so what can I do to help oxygen get to the roots and help it dry out faster? If tan spots developing on the true leaves (cotyledons still look perfectly healthy and dark green) isn't a symptom of overwatering, what could it be? *Edit: I also mixed a dose of calmag into the last gallon of water and watered with that before I finished, I assumed I might as well as I won't be watering again for a while. I feel like 1 dose of calmag dispersed among 4 plants shouldn't be enough to cause nutrients burn
I neglected to mention to only feed daily to run off once it has established roots. I start in solo cups and start feeding daily after 3-4 days from sprout.......then transplant after two weeks. If you started your seedlings in a large pot..........maintaining the correct moisture level will be a challenge. Your main problem is that you ran 10 gallons of plain water through the coco, messing up the CEC. Good luck.