Help yellow leaves? Used N already

[Legalize09]

i need help figuring out if i am on the right track with my plants. Im a first time grower and i have three plants under 2 flourescent lamps (metal halide lamp is on the way) and they are about 8-10 weeks. They looked good for several weeks and then i topped them. They continued to look good and green but the growth had slowed (i figured bc of the topping and so i didnt worry) recently within the last 3 weeks the bottom leaves were turning yellow ( i figured it was N defficiency) and i gave them a decent amount of cottonseed meal. i covered the top layer of soil with it and watered. Now i am here several days later and im wondering if the plant will continue growing yellow from the bottom up or will the yellow leaves turn back to a healthy green. Also how long would it take for the cottonseed meal to take effect? Im still new to this forum stuff so as soon as i fgure it all out i will post photos of the plants so you can see for yourself.

 

[Kash Krop]

If this works the affected leaves will show little if any improvment but it will stop the yellowing of any more leaves & growth rates will increase.I can't say how long this will take with the method you are using as I only use standard store bought chemical ferts as a boost to my homemade compost mix.Do you have a way to check PH?Very important to keep PH in a proper range for the type of growing medium ur using.I grow in soil so i try to keep mine between 6.3-6.9
Good Luck,
KK

 

[Legalize09]

the cottonseed meal is store bought also it is 6-1-1. I use regular potting soil in pots about a gallon size. i do not plan on growing them too big as this is my first time (and i got a second round about to sprout) and i would just like to get through this first time quick just for the experience. I dont have ph testers but i will get them soon.

 

[Legalize09]

bump