looks like fert burn, could you post pics of the whole plant? 1. hydro, soilless or Soil & brand name of soil ? 2. PH of reservoir solution? 3. PH soil runoff? 4. PH of water? 5. Age of plants? 6. What Fertilizer brand, dosages, and frequency? 7. lites, wattage & proximity to plants 8. Light cycle. 24/0,, 18/6,, 12/12? 9. In light cycle how long? 10. Room temps or reservoir temps
John Innes No2, 25% perlite, Soil PH 6.4 - 6.6, 5 weeks 1/4 strength nutes 24-8-16, every other watering every 2 days, 150w son t hps 12-18 inches away, veg 18/6, Room Temp 24/25 cent Heres some pics !
to me it looks like a calcium def or possibly manganese by the pics. often plants develop Ca defs their 3rd - 4th week of flowering, some strains use it more than others. there are many products available to add a boost, calmag is a popular one.
your soil is mostly compost, which contains alot of nitrogen in itself, additionally its been pre-fertilized with nutirents to last 5-6 weeks your plants is young and suceptable to nitrogen burn & basicaly was double dose fed with ph corrected water (6.5-6.8ph) flush the soil 3 times the volume of the pot to leech out the excess ferts eg: 1 gal pot = 3 gallon flush when you say , 1/4 strength nutes 24-8-16 what are the exact measurements are you using, from the suggested amounts on the box? or what youve learned from another grower just water for the next 2-3 weeks then begin to feed @ 1/8 strength to be safe, incase you didnt leech out all the available nitrogen
freshman i was typing when ya posted the pics of the whole plant, so i was refering to your initial pics. i still think Ca is gettin locked out somehow.