Bad watering habits causing brown discoloration?

[IndoorTropics]

photos this time.

Seen this now emerging before and after transplants into various seedling and transplanted mixes, purchased and pre mixed.

Is this a watering or fertilizer issue or something else?

RO water with biobizz calmag at 0.3ml.

 

[namvet25]

Don't no for sure what it is but it shouldn't be nutrient related at this early stage.Is this potting mix pure coco or a peat mix?

 

[NORB YIPPLS]

Looks like you spilled water on the leaves
I get this all the times

 

[IndoorTropics]

Looks like you spilled water on the leaves
I get this all the times

Oh that is very possible! Great thought!

 

[IndoorTropics]

Don't no for sure what it is but it shouldn't be nutrient related at this early stage.Is this potting mix pure coco or a peat mix?

Both started (1 still is) in seedling mix, a pure peat moss pre packaged product. then like the larger one transplanted into various soils (homemade) and pre packaged to comapre. Seeing the same across a few brands so think its me watering or perhaps like guy above said i dropped some water on it with a syringe perhaps.