Thanks for all your response.
I am growing northern lights, and Jackflash.
The container that they are grown in are 18 L, but only 3/4th are filled.
I usually give about 1 liter water in each, as when given only some of the water will run through,, is this wrong ?
I give the plants roughly the same concentration of nutrients, that is Biobizz line grow, and Alg-A-mic, half the amount suggested. One of the plants have been showing "rust" marks (northern light). Picture below. Why does only one of the plants show this when all the plants have been given the same. And the marks are still only on 2 leafs of whole plant. I started I thread asking for help, but still no response (
https://www.rollitup.org/marijuana-plant-problems/301090-what-can-causing-these-marks.html#post3765637).
Any reply will be appreciated. thanks.