heat stress? or?

-indoor or outdoor: indoor
-soil, soilless, or hydroponic : regular potting soil
-Soil pH: 6-7
-Water source : tap water with phosphoric acid added to lower the ph
-Water pH : 6-7
-Age of plant : 1 month
-Type of fertilizer : 1/4 strengh of atami b'cuzz grow added twice...1 week interval
-Lighting source and distance from plant : 6 CFL, 6 inch from plant
-Temperature (both day and night if you are running a dark period) : 85-90ish during the day, 75ish at night..
-Lighting schedule : 18/6
-Type of ventilation your room has: I fan blowing cool air inside, hot air escaping from top...


im wondering what this is...
only 1 of the 4 plants is doing this

any idea?

thank you

Heat stress indeed. Let me guess that one was closest to the heat source?

not by much....

but maybe he wasnt receiving proper ventilation since he was the one in the corner..

thank you stinky:)