Additional calmag under LED's?

[treesurgeon93 25]

Hi guys,

I'm currently growing under a combination of the Invisible sun LED's and CMH's. I was told by a couple of people to double Calmag (up to 2ml per litre) under LED's, but I think I perhaps over did it as i got black ash on a couple of autos I just ran - appreciate it may be down to something else but that's the only thing i've changed.

Any definitive advice to be had on CalMag front under LED's?

Thanks in advance

[tokenroll 30,409]

Up your main feed levels first and watch how they react, if no difference then add the calmag once a week and see how they go.

Black ash has nothing to do with your calmag have a rethink on your drying methods.

Toke...

Edited August 6, 2020 by tokenroll

[Guest]

What's yer water like? Just done an LED in coco grow with no need for any calmag.  If you've got decent hard water you shouldn't need it. 

[Larry Badgeley 8,284]

I added 2ml  Cal/mag per Ltr yesterday as my plants looked a little needy. I grow under LED's but Photo's. They look great today. I live in a soft water area so I just look at the plants and see what they need. I am about 3-4 weeks into veg under 20/4 light schedule. In flower I add a splash maybe once a week

[seb88 2,183]

Black ash sounds like it might not have been flushed of P/K possibly?

 

My tap water is 0.4 EC, I supplement with Mg because my water is lacking but don't get any Ca deficiencies.

[Smokebelch 19,746]

You have to read your plants dude, don’t just give them double of anything because some one told you too. I would only feed any Calmag if the plants tell me they need it.

Edited August 6, 2020 by Smokebelch

[treesurgeon93 25]

On 06/08/2020 at 2:20 PM, Slim Jim Free said:

What's yer water like? Just done an LED in coco grow with no need for any calmag.  If you've got decent hard water you shouldn't need it. 

Soft water up here mate. gonna drop back down to 1ml per litre and see what happens (Y) 

[treesurgeon93 25]

On 06/08/2020 at 6:20 PM, Smokebelch said:

You have to read your plants dude, don’t just give them double of anything because some one told you too. I would only feed any Calmag if the plants tell me they need it.

you're right i think mate. heard a lot of chat about doubling under LED's but i've learned the hard way. fortunately only on a couple of autos!

[treesurgeon93 25]

On 06/08/2020 at 3:00 PM, seb88 said:

Black ash sounds like it might not have been flushed of P/K possibly?

 

My tap water is 0.4 EC, I supplement with Mg because my water is lacking but don't get any Ca deficiencies.

hmm perhaps. i never go full strength with PK and I gave them the usual 14 day flush. perhaps not with a lot of run off is what i'm thinking. I never really got a decent fade on them either but couldn't wait any longer given the trichs maturing.

[treesurgeon93 25]

On 06/08/2020 at 2:05 PM, tokenroll said:

Up your main feed levels first and watch how they react, if no difference then add the calmag once a week and see how they go.

Black ash has nothing to do with your calmag have a rethink on your drying methods.

Toke...

thanks everyone for the feedback! 

 

Drying was bang on I think - 60% humidity and super low airflow - took them about 17 days to fully dry, so with that in mind i'd be inclined to rule the drying out? Could be wrong mind... 

[treesurgeon93 25]

On 06/08/2020 at 2:59 PM, Larry Badgeley said:

I added 2ml  Cal/mag per Ltr yesterday as my plants looked a little needy. I grow under LED's but Photo's. They look great today. I live in a soft water area so I just look at the plants and see what they need. I am about 3-4 weeks into veg under 20/4 light schedule. In flower I add a splash maybe once a week

yep i'm in soft water myself. I do think once you're well into flower it's definitely best to dial it down. I was pumping them full of it from the get go. rookie error!

[UKsFinest 3,558]

If you've been pumping them with it from the get go maybe that's why you're seeing issues?

[HippyHair 1,235]

Ah the old pumping method, rookie mistake.