Problem: Slight yellowing at their tips, also brown spots on the leaves.I think it's too early to tell for sure just from the leaves.
Below is the info the infirmary crew usually asks people to give. With more details on pH, grow media, and feed (brand/amounts), someone may be able to figure out what you could be missing.
Please fill in this form: (copy and paste part is below, this first one tell what specifically to include)
-Problem: (brief description)
-Medium/grow method: soil; soilless-- coco, or peat based like Promix, etc. (please provide the actual product name); DWC, NFT, etc.
-Feed and supplements used: include brand, dosage/strength, frequency of feeding and watering (alone); method-- by hand, drippers, rercirc' or drain-to-waste,... N-P-K #'s too if you can!
-Water source: RO/DI; tap- dechlorinated-?..... EC or TDS reading; pH (don't bother with this on RO/DI, do bother with TDS/EC though to confirm it's working well enough)
-Strain and age
-Climate: night and day ambient T and RH%; res' temperatures; any extremes in T/RH% exposure
- Light used: HID, LED, COB, combo of,... wattage; light cycle hours (20/4, 18/6 , etc.); distance to tops....
-Additional info: How long have the plants been affected?...How fast did symptoms appear?... Anything else you think might be relevant..
--Pictures including WHOLE PLANT PICS, and troubled leaves.. use normal light or flash as other light sources ruin color rendering, critical for diagnostics!
✂ - - - - - - - - - - -
(copy and paste)-->
Problem:
Medium/grow method:
Feed: and supplements used:
water source:
Strain/age:
light used:
Climate:
Additional info:
- Are you feeding at half strength based on the bottle labels or a specific fox farms schedule? What actual amounts (tsp/gal, etc) are you using? Have you been checking EC and pH after mixing?
- How often are you feeding vs. watering without nutrients?
- Are you doing anything to your tap water, or is that the pH straight from the tap? Do you know its EC / ppm? Can you find a water quality report for your city's water supply that shows how much Ca is in it?
For my next grow, i might be reconsidering using fox farm for soil and nutrients. In your opinion do you know of any soil and nutrients that are better and dont lack Ca or Mg?Overall, the leaves do not look very bad so far. I would keep an eye on them to see if they get worse. The threads below have good information that can help:
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Quick and Dirty deficiency picture depot (expanded to include other issues as well)
:toke: Folken- This thread is for compiling various deficiency pics gathered from all around,... the idea is to get several pics of each defc. and it's various symptoms, particularly the more atypical ones,... hopefully, to be included in a more comprehensive, consolidated thread for staff...www.autoflower.org
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Tutorial - A word on Nutrients
The proper use of “salt” based fertilizer to grow Auto Flowering Cannabis. Salts: Natural and man made any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation. Learning how to use salt based...www.autoflower.org
Based on your feed and tap water, it may be either a Ca or Mg deficiency (and/or lock-out due to high K). Thetrio has relatively high K, no Ca, and some Mg. You typically want those in a 4:2:1 elemental ratio to prevent lock-outs. Ocean Forest has some Ca in the soil, but it may be running out by this time in the grow. Without the column titles, I think your water quality report is saying you only have 5-27 mg/L Ca (or even just 7 mg/L) - which is pretty low compared to most tap waters.
I'd recommend watching how the leaves progress, and if they start looking more like Ca or Mg deficiencies in the pictures from the thread above, then I'd start adding 1 tsp/gal of Fox Farms / Bush Doctor Cal-Mag to each feed.
Is this another sign of deficiency in nutrients mg/ca? I see a brown spot on my stem. This is on my GSC auto week 7.K, Ca, and Mg have to be managed to be in the correct proportions. Whether you are too high or too low in one element depends on the overall combination of your soil, feed, and source water.
More often, people run into problems from too much calcium, which can be harder to fix. It's not a bad thing that your tap water is so low. If the cal-mag fixes it, and everything you're doing works for you for the rest of the grow, then I'd just stick with it for the next grow. Otherwise, you may have to change up your feed schedule too, etc.