I do not know what is happening to my plants, please help me SETUP: 4 Violator Kush (Barney seeds) and 4 LSD (Barney seeds), beginning of third week of flowering, under one 400w hps (cool tube) and 2 x 200w fluorescent, 12 liters pots (with "rich soil" prepared specifically for marijuana by an expert and famous local grow-shop and used by almost all growers in my town). temp 30C, humidity 40 - 45 %. Group view: Nutrients: BioBizz 1ml BioGrow + 2ml BioBloom + 1ml TopMax x liter given every time I water the plants. Watering schedule: In the past 2 weeks (from the beginning of flowering) I had watered every other day (the first 5-6 centimeters of soil were dry, but I think it is too often). From now on I have decided to water one time in 3 or four days (when the first 2 inches of soil are completely dry). View of 1 Violator Kush, and 1 LSD Problem 1: I think all the plants are overwatered but this LSD had started to yellow her leaves (first older leaves and now It's beginning to affects top, young leaves). I think it is magnesium deficiency, what do you think? Problem 2: This violator is yellowing (from bottom to top) in another manner, I think it is a potassium deficiency, what do you think???
it seems like there would be a much more efficient way to hang those lights.... have you tried putting them vertically with reflectors? seems like it would make a night and day difference..
They all look deficient in magnesium & phosphorus. Lay off the grow nutes. What is your pH? PPMs? Don't add any nutes unless your soil runoff is in the 6.4-6.8 range. You may even want to wait a few days before adding anything if you had a bad pH, the nutrients could have been tied up in the soil, but a pH above 6.5 will release them. -OSUB
Definitely over-watered which in turn will cause nutrient deficiency. Also I would recommend investing in at least another 400 watt hps(approx. 55,000 lumens) instead of the florescent light. You will never see the full potential of your plants! The square footage of your room times 3000 is a good rule of thumb figuring out how many lumens you need.
If you don't want your harvest hijacked you had better flush... ph of the root-zone is driven low by excess salts. Flush with three times the volume of substrate with properly ph water to at least 7 and run it through for correction.