Hello growers!

This is my first post here in this great forum. I've been reading a lot and started my first grow, and until now I had no problems.

Last week two of my plants started to develop burn tips on some of my lower leaves. It quickly spread to most of the leaves, some with more intensity and others with less.

I read a lot and saw loads of pictures of problems and deficiencies, but could not deicide if this is a Nute Burn or some kind of deficiency (Potassium?). It's hard for me since I never saw any of them in real life (first grow!).

Hope you guys can help me!

Here is the Troubleshooting form followed by some pictures:

E-indoor or outdoor = Indoor
E-soil, soilless, coco, aero, or hydroponic = Soiless
E-specific medium = SunshineMix + Perlite
SCL-Anything you have added to the soil = Perlite
SCLR-Soil or slab runoff pH = 6,3
E-Water source = Mineral Water
E-Source water pH = 6,7
E-Age of plant = 5 weeks and 3 days
E-Type of fertilizer = Biogrow (Biobizz)
E-Rate of application = 1ml/L every watering, then when the problem appeared every other watering
E-Lighting source and distance from plant = 400 W HQI, a palm distance from the tops.
E-Air temperature (both day and night if you are running a dark period) = 82,5F (day), 79F (night)
E-Air % Relative humidity = 68% to 75%
E-Lighting schedule = 18/6
E-Type of ventilation your room has = One large fan taking air from the cooltube and grow, one smaller fan bringing fresh air, plus one small fan for air circulation.

Thanks for the help! :smokin:
AnomanderRake Reviewed by AnomanderRake on . Fert burn or K deficiency? Hello growers! :) This is my first post here in this great forum. I've been reading a lot and started my first grow, and until now I had no problems. Last week two of my plants started to develop burn tips on some of my lower leaves. It quickly spread to most of the leaves, some with more intensity and others with less. I read a lot and saw loads of pictures of problems and deficiencies, but could not deicide if this is a Nute Burn or some kind of deficiency (Potassium?). It's hard Rating: 5