LEDs causing magnesium like issues

[Tattooguy8]

Been lurking for years finally decided to ask some questions!

Been battling magnesium deficiency looking issues with slow growth and poor root health for a few years now and I just can’t figure it out.

Current situation
Peat with 30ish % perlite
Gh flora series at 2.0 ec. 2.5 ml of
2.5ml Cal mag included in ec
Ph 6.5
Room temp 84
Leaf temp right around 78
Rh 55-60
Ppfd between 150-200
24 hour light cycle in veg
Lights mars hydro fc4800 7’ off the
At 20ish percent
Using ro water at the moment

Been doing this since 96 under hid of course. A few years ago bought a new house and decided to go led. Problems ever since, especially in veg. Magnesium sick spindly, stretchy purple stems. I don’t flower sick plants but if I throw those same sick plants in my flower room in a week they will look so much better with no other changes. Not perfect but acceptable.

I’ve tried everything. Low ec, high ec, tons of runoff, no runoff, 50% drybacks to just at wilting drybacks. I’ve tried coco and peat. I even went back to cmh. Still had the issue but it was slight. Almost impossible for me to get above 250 ppfd in veg. The only thing that kind of remedies the issue is a super high ec. Like 2.5-3.0. I don’t know how everyone can run 1.4-1.6 ec at 400 ppfd at 78 degrees. My plants would literally be dead. I’m obviously having either a root zone issue or transpiration issue or both.

Another related issue, I sprout seed under a t5. Beautiful green growth with super stacked nodes. As soon as I move them to the LEDs the don’t grow new nodes they just stretch their asses off. I have to top them multiple times till they slow down and start to actually grow.

Having to add so much heat into my veg room and still have sup bar results is starting to get old. My plants would literally be dead if my room isnt above 80 degrees with a super high ec. I feel like I’ve read every leveant thread on the internet but there’s no solution. Everyone just disappears. I’m betting they go back to hid.

Sorry for the long post. Please help.

 

[orggrwr]

I've had slight magnesium issues with some strains under led but nothing like you're describing. My issues are usually solved pretty quickly with Epsom salt. It might help to put them on a 18/6 or 20/4 light schedule for veg. The 24 hours of light may be stressing them and making the situation worse. Hope you get it figured out, good luck.

 

[Tattooguy8]

I've had slight magnesium issues with some strains under led but nothing like you're describing. My issues are usually solved pretty quickly with Epsom salt. It might help to put them on a 18/6 or 20/4 light schedule for veg. The 24 hours of light may be stressing them and making the situation worse. Hope you get it figured out, good luck.

I have tried 18/6 and 20/4. It did seem to help a bit but the plants stretched a bit more. I already have an issue with stretching from having to run such a low ppfd dli. The other issue is heat for me. After lights come back on it takes a while for the room to get back to proper temps. I’m in a basement that is cooler than the rest of the house.

 

[Bigalmoby]

I’m far from a pro but I know that peat hold moisture a lot

Having that said root problem I would say you have moisture issues bad dry backs then you add food and you get pockets that hold nutrients with no roots builds up adds up and voila
Hope I’m wrong good luck

 

[orggrwr]

Maybe a cold root zone being as it's in a basement. Do you have something under the pots to keep them off the cold floor?

 

[Tattooguy8]

I’m far from a pro but I know that peat hold moisture a lot View attachment 2600315
Having that said root problem I would say you have moisture issues bad dry backs then you add food and you get pockets that hold nutrients with no roots builds up adds up and voila
Hope I’m wrong good luck

I’m sure that plays a part but I add a decent amount of perlite to what already exists in the mix. Up until I started with LEDs all I bet used was peat. Never had these issues. While I don’t believe peat is the actual issue I do believe what you described does happen to a certain degree. The question is why does it take so long for them to settle in sometimes? Low ec and they are sick, high ec they look almost normal but salt issues happen a few weeks after transplant regardless of how much runoff they get.

 

[Tattooguy8]

Maybe a cold root zone being as it's in a basement. Do you have something under the pots to keep them off the cold floor?

I have them raised up on saucers that catch runoff. 2-3” off the ground. Maybe that’s not enough? I learned a long time ago not to put pots directly on concrete. Cool roots could be possible but with room temps at 84 degrees is seems unlikely.

 

[BearWater]

Got any pics?

 

[Tattooguy8]

Got any pics?

This is at its worst. I recently built a new veg room and struggled getting it to the same parameters as the last area. My truncheon meter was reading super low at the same time and I didn’t know it. I thought that was the solution to my problem so I went down to 1.4 ec and they got really bad. They seem to be getting better now but it’s a ton of work. The issue is always just trying to rear its ugly head.

 

[BearWater]

View attachment 2600317View attachment 2600318View attachment 2600319
This is at its worst. I recently built a new veg room and struggled getting it to the same parameters as the last area. My truncheon meter was reading super low at the same time and I didn’t know it. I thought that was the solution to my problem so I went down to 1.4 ec and they got really bad. They seem to be getting better now but it’s a ton of work. The issue is always just trying to rear its ugly head.

just spit balln here. Could it be the ro water?

 

[Tattooguy8]

just spit balln here. Could it be the ro water?

Could play a part for sure. Seems like they look the best with tap ro 50/50. I mean the difference is marginal though. The reason I went away from that is for problem solving. My tap water ec changes through the year and that variable makes it hard to diagnose things.

 

[BearWater]

Could play a part for sure. Seems like they look the best with tap ro 50/50. I mean the difference is marginal though. The reason I went away from that is for problem solving. My tap water ec changes through the year and that variable makes it hard to diagnose things.

Have you ever tried just the tap for a whole run?

 

[Tattooguy8]

The most confusing part of this is if I put these girls in the flowering room with almost identical parameters they perk right up. Not perfect but respectable looking plants. I go from struggling at 200 ppfd to 600 ppfd.

Someone mentioned earlier root ball temps. I guess that’s the only thing I haven’t played with. Should I be heating the root balls directly? Sounds pretty crazy to me.

 

[Tattooguy8]

Have you ever tried just the tap for a whole run?

I have but that was back when I moved into this place and got the LEDs. My tap water goes from 2-300 to 600 ish at times. I think I quit using it pretty quick to rule it out.

 

[BearWater]

have you tried turning the light down even more? I can flower my plants on the lowest power with my led. And it’s not inched away either.

Sounds like you have a couple ideas though! Good luck : ) keep us posted if you feel like it!

 

[Tattooguy8]

Have you ever tried just the tap for a whole run?

It’s funny because my brain wants to think it’s the house or the air in the house haha. All these issues started here. They still persist even with hid just not nearly as bad. My veg room plants look pretty good with metal halide but I don’t like the way they grow. I get pretty lanky growth with mh but I think it’s from the same issue, it just shows different?

 

[Tattooguy8]

have you tried turning the light down even more? I can flower my plants on the lowest power with my led. And it’s not inched away either.

Sounds like you have a couple ideas though! Good luck : ) keep us posted if you feel like it!

I mean I can but they seem to stretch more. I’m averaging 180 ppfd in that room right now. Lights are 7 feet off the ground at around 15-20%. Some of those girls are four feet tall and they get sick if I touch that dial at all. So weird.

 

[BearWater]

Yeah that doesn’t sound like that’s the issue.

I mean I can but they seem to stretch more. I’m averaging 180 ppfd in that room right now. Lights are 7 feet off the ground at around 15-20%. Some of those girls are four feet tall and they get sick if I touch that dial at all. So weird.

Hey sorry for all the questions. How many strains have you run with all these issues? Same strain. Different strain? Clones?

 

[Tattooguy8]

Yeah that doesn’t sound like that’s the issue.



Hey sorry for all the questions. How many strains have you run with all these issues? Same strain. Different strain? Clones?

No way I appreciate you trying to help.

I have roughly 12 keeper moms I’ve found over the years that I’m continuously running and I’m constantly in a pheno hunt with random breeders looking for new special genetics. I do a bit of pollen chucking as well. Some of the plants can handle the stress better than others but the issue is always just out of sight.

 

[Tattooguy8]

Yeah that doesn’t sound like that’s the issue.



Hey sorry for all the questions. How many strains have you run with all these issues? Same strain. Different strain? Clones?

Check this out. This was a mom I had in a one gallon. This plant was in this pot for four months roughly. Way too long I know but I’m always fiddling with stuff. I decided to break open the root ball and most of the roots were growing between the pot and media. So confusing.