CMH plant issues

little bit of background first: my original tent is running a growers choice 630ns light fixture with their 10% lumen boost and a 3kr 315w bulb + a 4k 315w bulb. that original tent i can germinate to flower underneath the hood, directly, with no issues what so ever. I run coco tupur- botanicare cal mag plus 5ml a gallon, megacrop 4g a gallon and slf100, 5.8 ph. the original tent takes these feeds and light levels no issues whatsoever. plants get as close as 8 inches to the hood in flower with no light stress symptoms AT ALL.

My plants in that tent were outgrowing the hood in height so i purchased an identical, growers choice 630ns CMH hood. I took those plants under the original hood and moved them to the new hood and they crashed within a week. Growers choice insisted it was light stress and environment combo’d with lockout.I have restarted 5 more grows since then under that CMH all with similar results.

I purchased a tent, ac infinty all to dial in a new environment exactly as my orignial tent. I removed one bulb and ran only 315w with slightly better results. hitting preflower i added the 2nd 315w bulb and lowered the wattage to 480w instead of 630w. they continue to do worse and worse. I lowered the light schedule from 24 hours on like I normally do in my good tent to 18 hours on. still no improvements.Attached are a few photos of the latest plants and what they have done over 3 days under both bulbs dimmed down to 480W from 630w. the first photo should be a photo of a plant started in my good tent with 10% lumen boost, started from seed with no issues whatsoever.

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No pics but that sounds very odd. There must be some yet to be seen difference between the two spaces.

The light fixtures should be identical, right? Try switching the light fixtures (bulbs and all) between the two tents and see if they still behave the same. If the new tent is still messed up then you know it must be something else.

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There’s photos attached to the imgur link. I’m waiting for new bulbs. No way I would risk plant genocide on 2 plants that are doing successful in the original tent

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What beacher said. Strange.

What kind of feeding schedule? How often do you feed, to runoff?, ec/ppm in. and run off PPM if you know. Temp/humidity matters for sure.

I tend to have fewer issues running my coco ph between 5.9 and 6.3. I let it swing the range.

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I’m running similar feedings as my main tent, 5.8 ph 5 ml calmag plus, 4g megacrop. I think that was about 800 ppm. I dropped nutes recently because it seemed nitrogen toxic to 500 ppm with 4 ml cal mag plus and 2g megacrop to flush out the system for the next couple of feedings. On those waterings they were reading 800 ppm out and 700 ppm out… I water every day until run off, royal gold suggested letting the tupur dry out some. In my main tent I can let the tupur literally go dry with no issues or water 2x a day no issues. My main tent goes up to 84 degrees and lately in flower I have humidity 35-45% even with a smaller auto in veg just now hitting preflower. The fubared tent is 78 degrees and 50% humidity. I did have fans kinda whipping them for a while but I shut one off and only have another at medium setting breezing em.

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My buddy does the same style of grow. Tupur and daily feedings. Cranks out some killer buds. Under HPS just so happens. I have never grown in Tupur, only coco.

My current style is coco in small pots and automated multi-feeds per day once they are ready for it. Also feeding lower ec, less run-off, more often.

I was looking up the PH for Tupur…
Below is from the Royal Gold website.

Feeding/Watering:

-Allow your container to dry out after the first two waterings to enable your roots to explore and become established within the container.

-Make sure your roots are established before implementing an automated feeding schedule.

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Ya good thought, don’t jeopardize the plants that are doing ok. Get a light meter app for your smartphone and take some measurements in various areas around both tents, maybe you’ll see some drastic differences.

Same batches of coco and nutes for both?

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Same coco, same nute line i ran before on another plant in my good tent without any issue. I’m pumping out 8oz+ per auto in my good tent, massive bushes this time too 3.5 feet by 3.5 feet super cropped with massive colas. Not like I’m dickin around and don’t know what im doing so this is real strange that despite all these drastic measures I’ve taken things still deteriorate or don’t particularly improve. New growth looks to be better than the older growth that is shiny but it usually goes south after some time. Keeping an eye on them since I reduced the nutes to half dose

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That’s such a piss off lol. I hate having problems like that that make no logical sense readily. Try the light meter app, and also maybe just go sit in each ten for a few minutes and observe… sounds weird but you might notice something.

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definitely made sure they were established in starter pots before moving to 3 gallon containers and then only watered once every several days and moved up to every day waterings. Then moved the 2nd cmh bulb in and cranked down to 480w following growers choice reccomendations. Went to shit so did 22 hours for 3 days. Then 20 hours. Then 18 hours right now when my main tent is 24 hours no problems

Dang. The light dealio has me stumped. But then, I have only ever used single 315w hoods with Philips bulbs. And no dimming.

I was just asking general coco questions since thats all I grow.
Also been down a long road with MC from v1 thru v3. Most common issue I had was exessive K in flower due to me slapping them with boosters. lol Some cal/mag issues until I learned more about coco. The 1part is subject to precip, IMO.

I pound them in my main tent with boosters no issues. Up to 1.5g of veg plus bloom shine formula I don’t think its 1p nutes

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This is an interesting puzzle, you have minimized the variables.
As beacher said, swap the components (I’d start with the bulbs). Standard debug protocol when playing “one of these things ain’t like the other”, is one piece at a time.
The phone app is ok for A vs B comparisons.

Side question, do these CMH bulbs shift/change their spectrum when dimmed?

Cheers
G

I think it changes it slightly but gc manager said there shouldn’t be any ill effect all it’s doing is sending less photons to the plant. New bulbs are coming here in 2 weeks, hopefully sooner. Had to pocket the cost right now but need to get things rolling. If things turn out better I guess I’m going to have to talk to gc about that situation.

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Growers choice decided to send me new bulbs after reaching out to them again for their continued troubleshooting. They wanted to see some photos of the bulbs so I sent them closeups of the bulb components. After sending the photos and inspect the bulbs themselves I noticed a crack on the inner 3k bulb and a larger crack on the 4k bulb outer bulb. Definitely not plugging them back in after seeing that and I think that’s what my issue is

Definitely a wise decision, they are not as dangerous as high pressure projector bulbs but not something to take lightly either. :+1:

Cheers
G