Week 9 Mg or Mn def or natural fading ? Help!

[randomgrower]

Problem: Interveinal chlorosis, yellow and dry tips, overall yellowing.

-Medium/grow method: soil, recycled Biobizz light mix + 15% worm castings/ biochar.

-Feed and supplements used:
- Day 0 60g Greenhouse Feeding Bio grow 7-2-4 mixed with the soil
- 2 weeks later 4 tbsp Dolomite + 1 cup lava rock dust (suspected ph was on the low end).
- Day 35 top dress with GHF bio bloom 4-9-9.
- Otherwise Enhancer with Kelp/ Humic acid and microbes every 10-14 days.

-Water source:
Straight from tap. 300-350 ppm/ pH 7.3
Analysis says 90 ppm Ca, 9 ppm Mg, 25 ppm Na. Acceptable range for Fe, Mn etc.
My water provider is not using chlorine.

-Strain and age
CBD Fix zamnesia, 60 days old.

-Climate:
Day time: 23-25*C/ 45-50%/ VPD 1.3 kPa/ LST -1.5*C
Night time: 19*C/ 50-60%

- Light used:
LED 150W/ 24” from canopy @ 90%
PPFD 500-650/ DLI 30-42


Hello people,
finishing the CBD Fix auto soon but it started fading a couple of days ago. It is 60 days old and normally ready in 2 weeks, max 3 weeks.

At first sight the fading looks more in the upper part of the plant so I thought about light stress but some leaves with less exposure to light than others will show symptoms also.
Buds under the top ones remain fairly unaffected and the very old fan leaves are still normal green with no symptoms at all.

I am confused! The interveinal pattern tells me it is Mg but the oldest fan leaves are unaffected! It looks like no charts!

Now I tend to think that my tap water has high calcium and low magnesium so excessive calcium from the dolomite is locking out Mg, Mn and other stuff.

It seems a bit too early for a natural end of life fading too..

please help me!
cheers

 

[namvet25]

Make sure your intake water is near 6.5 ph and you usa a little cal/mag with light bloom nutes,

 

[Don Manzoni]

Definitely Ph range is high from tap, use some - to get it in the 6.5 range + I suggest grabbing some Epsom salt and foliage spray mixed with room temp water for a fast fix, try to not spray on buds but even if it happens should not be too much issue since you still have weeks to go.
I have problems also using led lights idk if that’s the reason but other people have too. nice grow

 

[bearhair]

if your on city water and they say they arent using chlorine theyre using chloramine. even worse.. but any way id bet @Mañ'O'Green could be of help. give him a minute.

 

[Cannaficionado]

If you're using leds with it that far away you shouldnt be experiencing light stress.

What is the ph of the water after nutes are mixed?
You should be around 5.8-6.0. I believe your problem is coming from lockout. Everything looks fine besides the described problems. Looks like its growing fine otherwise.

It is possible you have a magnesium deficiency. But if so that could be due to multiple reasons. You could have too much phosphorus, or ph could be out of balance. But interveinal chlorosis is the sign of some toxicities, and also the sign of some deficiencies as well. The most common being mag deficiency.

Check the ph of your water after mixing nutes. If its in the desired range, maybe reduce the feed by 1/4 dosage and also through a 1/2 tsp to a tsp of epsom salts as a top dress or use the same amount per gallon in a foliar spray and spray 10-15 minutes before lights out. The foliar application should only be done once a week. If your plant will be done in less than a month I would foliar spray rather than top dressing though. Either way though if it doesnt get worse I wouldnt stress out too much about it.

 

[bearhair]

5.8 to 6 ph is for hydro or coco. Should be closer to 6.3 6.5..

 

[N/A-Greengo]

5.8 to 6 ph is for hydro or coco. Should be closer to 6.3 6.5..

 

[Lil Dab]

if your on city water and they say they arent using chlorine theyre using chloramine. even worse

And they need to be treated they won’t gas off like chlorine will.. I believe folks use vitamin C to treat for chloramines

 

[Lil Dab]

And in my personal experience 300-400 ppm tap water is too high.. Mines floats in that range all year the best thing I have found to do is cut it with RO water by 25-50%.. I cut mine to 25% <100ppm