deficiency when co2 kick-in

[saimon]

i never asked for help in my entire life about MJ problem. i always discovered everything by myself, but this time, i need help.

i using technaflora product line, with fully automated system. my system is trouble free and work very well. i use vertical gardening with rockwool slab. i start co2 (1300ppm @ 85F) at the beginning of weeks 3(flowering). about a week after i begin having a yellowing of leaf and brown spot on them. i water every 2 hours (due to vertical position) for 6 minutes @ 1000ppm. the setup work perfectly on non co2 enrichment.

i use 1000ppm as im watering more often.

i have a picture here, as i've been on a trip for 4 weeks, i could not fix before leaving. so im currently on week 7.

the problem still arise couple days after co2 enrichment.
any help would be appreciated.
i think its a nitrogen deficiency, but not sure....

 

[2clean]

U have same problems like me. Mines happens at day 38 flower. Follow my journal. These leaves will get worse in 24 hrs n dry and fall off. The rust will increase. Happens usually in larger leaves. Have u grown this strain in the past. I would bet it's from mute lock out.