This is a leaf symptom I've seen before but can't figure out what is causing it...

[tilopa]

These are seedlings that are now about a foot tall.

1 gallon pot with roots organic soil.
Watered only when pot has dried down. Basically been watering every 4 days or so.
Watered with plain chlorine filtered water, no nutes.

These are outside under shade cloth, the temps are high at mid to upper 90s.

What is causing this?

 

[furnz]

I would transplant to a bigger pot.
The plant has depleted all the nutrient in the pot most likely and you may be underwatering.

 

[Wizzlebiz]

Thats no seedling.

Transplant into new soil will probably fix your issues.

1 gallon pot is not idea anymore for that vegging plant.

 

[tilopa]

Thats no seedling.

I just meant that it started from seed, if that even matter.

There is no way I am under watering, but I might be under nuting as I've not added any nutrients.

I'll try transplanting and giving them some added nutrients.

 

[Wizzlebiz]

I just meant that it started from seed, if that even matter.

There is no way I am under watering, but I might be under nuting as I've not added any nutrients.

I'll try transplanting and giving them some added nutrients.

The roots become bound in a pot that size. The nutrients become used up.

When you transplant you are putting the plant into a new nutrient rich environment. You will not need to add additional nutrients for a couple of weeks after transplanting.

That's why I suggested doing the transplant. It will solve alot of issues with very little work.