A bit of yellowing - What do you think?

[Weekender]

Folks I am looking for some help from your vast knowledge of this little green plant. As you can see there is some yellowing on plants here and there. The veins are visible on the leaves of some plants, I believe the plant is missing something.
The plants are Big Bud and Kush, different breeders, feminized, all from seed.
In Fox Farm soil
18/6 lights
12-4-4 nutrients, weak solution twice per week.
Indoor for now, they will be outside in a month and I want them to go out healthy as can be.

 

[Kriaze]

It looks like a CalMag deficiency, are you using LED lights? If so then plants grown under these types of light usually require more CalMag. If it's not LED then maybe your water is lacking, add some blackstrap molasses to your watering schedule and it will clear up.

 

[Dan Ultra]

It looks like a CalMag deficiency, are you using LED lights? If so then plants grown under these types of light usually require more CalMag. If it's not LED then maybe your water is lacking, add some blackstrap molasses to your watering schedule and it will clear up.

Could you explain this a little more? What exactly would be lacking in his water that molasses would clear up a deficiency without knowing what is causing the deficiency? Cal/Mag?

 

[Major PITA]

Possibly a little over-watered.
Plenty of 'N' I think.
I'd look into a little more 'P', 'K', Cal/Mag and make sure the micronutrients are all being covered.

 

[Kriaze]

Could you explain this a little more? What exactly would be lacking in his water that molasses would clear up a deficiency without knowing what is causing the deficiency? Cal/Mag?

If they are using RO water (reverse osmosis) then there's a good chance that they would be lacking Calcium and Magnesium trace minerals. As the leaves are yellowing between the veins which suggests these minerals are in short supply, using blackstrap molasses would provide these nutrients. They could also go and spend more on chemical CalMag but blackstrap molasses is cheap and easy to get hold of, plus it will provide the same nutrients.

 

[Weekender]

I use plain tap water no RO. I check PH, I need to bring it down to 6.5 from around 8. I then add 1/2 of recommended liquid nutes to the water and feed while watering once per week. I am using T5 lights.

 

[Dan Ultra]

I use plain tap water no RO. I check PH, I need to bring it down to 6.5 from around 8. I then add 1/2 of recommended liquid nutes to the water and feed while watering once per week. I am using T5 lights.

Add nutes and then pH.

Most nutrients are going to lower your pH as they are slightly acidic, so you'll want to pH the water AFTER adding them.

 

[Major PITA]

I use plain tap water no RO. I check PH, I need to bring it down to 6.5 from around 8. I then add 1/2 of recommended liquid nutes to the water and feed while watering once per week. I am using T5 lights.

Always add nute's first then adjust the PH.
Most nutrients are acidic. My water is 7.0 from the tap but after adding the nute's it lowers to 6.3. I never need to lower the PH of my feed solution.

 

[Mpfstc]

Always add nute's first then adjust the PH.
Most nutrients are acidic. My water is 7.0 from the tap but after adding the nute's it lowers to 6.3. I never need to lower the PH of my feed solution.

Amen! I wish I would have known this when I first started out.

 

[Budd Aldrin]

A simple dude like me would just use wood ash. But if you have funds, I recommend liquid bloom and kelp ferts with a high K. Or MG sulfates.

I use just a little Cal-Mag only when my tips are white to prevent this deficiency.

Possibly a low ppm count in your water?
I also have dolomite and castings in my soil to have a healthy photosynthesis production.

 

[Budd Aldrin]

Oh. The ash thing is old timer shit. I wouldn't recommend it. It could cause more problems if not used correctly. My bad.

 

[Weekender]

Hey I appreciate all of your thoughts on this issue. I think I may be just over watering as I did give them a heavy dose when I trimmed last week. I will give them a good dry period and see if goes away. If not, I will purchase some of the Cal/Mag, it has been recommended before and I have eyeballed it in the grow shop. See if that gives them added vigor.
Hey Budd Aldrin I may try some ash in the water but if that kills'em. Dang you Buzz

 

[dick23rk]

I would have to say this is just straight magnesium deficiency IMO. I have had calcium def myself and it starts out as small round rust looking spots in random areas of lower leaves. The only rust spots I can see on your leaves is right around the outside edges which says to me this is getting closer to the middle stage of magnesium def.

This was my calcium def.. Something else came along with this a week later since normally when you get a lack of calcium you are getting a lack of something else along with it, but I wasn't to sure what it was a mixture of.

 

[Weekender]

I did purchase some Cal-Mag and have added this to the watering schedule, some just getting the first bit this morning. I tested the solution on a few and they did not die at least not in the first 48, so I added it to all juveniles schedule. It will probably be a week before I see any results both good or bad. They are looking ok now.