Welcome to UK420

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more!

This message will be removed once you have signed in.


Smokebelch

Could my Scopes be too Bright

68 posts in this topic

I am looking for a bit of help as I am struggling with my plants showing signs of MG and Cal deficiencies after 2 weeks in flower. The plants are obviously locking these out as I have tried fixing it with some CalMag but this doesn’t work and they slowly get worse until the end.

 

Its not a complete disaster as I am still pulling 3oz of nice flowers off each plant but I am used to seeing lush green and healthy foliage right to the end and at the moment my plants are looking pretty ropey after week 2 of flower and it doing my head in.

 

It’s got to be the lights are too bright as the the plants looks healthier where ever the foliage is in the shade and it’s the only thing I have changed.

 

I am running 2 x 250w scope strips in a 120 x 120 tent and I have slowly been dimming them down, first to 460w then the other night I dropped it down to 370w.

 

The temps are still fine at this wattage but I am now worried I am dialling it down too much, I am a bit useless with the tech side so some adivise would be great.

 

I have a plant that’s been in flower 2 weeks and it’s looking ok so far so hopefully I am right about them being set way too powerful.

 

Plant tops are 17 to 20 inches below the plants. The temps at the plant tops vary from 28 to 30, I have another probe halfway up one plant and it’s usually 27 to 29c. Night temps vary from 22 to 24c. I have a heat map that’s keeping the roots above 22c.

 

I am hoping that lowering the power of the lights will fix my probs, the main question I have is how  much can I lower the wattage before it starts to affect the yeilds and what do you recommend on height of the lights bearing in mind my temps are pretty stable whatever height they are at.

 

I think my first grow was a success as I had the lights a lot higher but I want to try and lower my running cost so lower watts are a winner for me.

 

I don’t like showing off ropey looking plants but I will get some photos of the worst ones later. The only plant that looked uneffected was my The New, everything looks like it’s slowly starving itself of Calmag.

9 people like this

Share this post


Link to post


@Smokebelch I would not be running them any more than 400 watts in your space m8, not saying it's the problem but easy to rule out. What I find is if I don't feed with grow nutrients until week 3 12/12 I would get the same thing. Now I do use calmag once a week at 1/3rd strength from veg to last two weeks of flower.

Toke...

Edited by tokenroll
12 people like this

Share this post


Link to post

@tokenrollCheers for info dude, makes me feel like I am on the right track by lowering the watts,  I am pretty sure that’s what is causing my problems, I guess we will find out over the next couple of weeks.

 

Edited by Smokebelch
5 people like this

Share this post


Link to post

I think I may have had the same issue @Smokebelch I'm a bit confused about how much watts. I thought it was recommended 30-35 watts per square foot? I'm in a 1.2 x 1.2 tent so I set the light at 480 watts. So if my sums are right this would be 30 watts per square foot. 

 

2 hours ago, tokenroll said:

@Smokebelch I would not be running them any more than 400 watts in your space m8, not saying it's the problem but easy to rule out. What I find is if I don't feed with grow nutrients until week 3 12/12 I would get the same thing. Now I do use calmag once a week at 1/3rd strength from veg to last two weeks of flower.

Toke...

Hi toke, are you suggesting 400watts is plenty for this space or more of a starting point? This would be 25 watts per square foot I think. Also when you say you use calmag once a week, is this instead of feeding with grow nutrients up until week 3 or both together? Thanks

 

3 people like this

Share this post


Link to post

@Greenlittlefingers 30-35 watts per foot is what I would go with if your hanging the lights higher for the spread, if canopy is equally covered. IE around 2-3ft above the canopy. If all is dialled in it there should be no problems. If top say 8 inches of the plant starts showing defiences you can bet it's light stress. So it's simple hang the lights higher or turn them down.

If you have loads of strips or boards to cover the canopy even at say 8 inches then 25 watts per square foot will be plenty. Everyones space and growing style etc is different and requires the grower to use there head with how much light the plants can take. With these leds its not just a fact of 30 watts per square feet as they do produce more usuable light and the more efficient they are run they can produce more. So more leds at less power can achieve the same or more use able light at lower power.

As for the calmag that goes into the res first to give 0.2 EC above the taps background EC. In my case tap is 0.4 EC so I add 0.2 EC of calmag total then is 0.6 EC then I add nutrients to get to required EC and then PH to correct level. Im in coco so no idea about dirt.

The way I grow is certainly not the way the average tent grower is going to use their lights.

Toke...

Edited by tokenroll
9 people like this

Share this post


Link to post

Thanks for the info @tokenroll  I thought I was erring on the side of caution with 30watts. I'll start them a bit less next time. :yep:

3 people like this

Share this post


Link to post

Tokes advise is always solid. Dim it and raise it. 

 

I hope you resolve this @Smokebelch i do suspect you're correct with it being too much.

 

-Adam.

7 people like this

Share this post


Link to post
39 minutes ago, Greenlittlefingers said:

Thanks for the info @tokenroll  I thought I was erring on the side of caution with 30watts. I'll start them a bit less next time. :yep:

Anytime your more than welcome.

4 people like this

Share this post


Link to post

@GreenlittlefingersDo you have same set up as mine dude, 2 x 275w, mine are on custom built frames and bolted together and I literally have wall to wall lights in the 120 x 120 area of the tent.

 

@tokenroll Thanks for the detailed explanation, seeing as I have wall to wall strips in my tent I am sure it is the 500w of LED lights thats made my plants lock stuff out.


Seeing as I have so much led coverage in my space I may even dim them down a bit more to 350w and keep them at around 20inches above the plant tops as my temps at the canopy are still the same as when they were running at 500w.

 

@diyledukI am sure it’s the lights being too bright and now I am taking steps to fix this which will also lower my running costs so this could end up being a god send, lower electric bill is always very welcome and one of the reasons I changed over to LEDs. 

 

The thing is even with the problems I am still yielding more and the flowers are still nicer than the HPS stuff that looked really healthy. I think if I can sort this out then it will be even better.

 

Thanks for the input everyone, I will update this with how things pan out over the next month or two as I add new plants into the dimmed down 350w flower tent.

Edited by Smokebelch
7 people like this

Share this post


Link to post

@Smokebelch I've got the cxm550 cobs, so not the same but I think I've been getting the same issues with too much light. Hope you get it dialled in. I'll be interested to see your updates. Best of luck.

3 people like this

Share this post


Link to post

@Greenlittlefingers I deffo think it’s the lights causing the probs, these LEDs are more powerful than they look.

 

Good luck with yours too dude, post your results in here for future LED users to reference.

2 people like this

Share this post


Link to post

This evening I managed to get a couple of the worst looking plants out and got some photos of them, as you can see they are not very happy, I am convinced its being caused by me cooking them with too much light. 

 

Adam has very kindly sent me a PAR meter today and when it arrives I am going to call him on the phone and we are going to get my lights set up properly, now that is what I call good customer service.

 

Some good news is the Dirty Larry that I put in when I turned the lights down to 350w is at 2 weeks now and is looking much better than the plants that were under 450w at the 2 week stage. Its got to be the lights causing this as I haven't changed anything else. One thing to note is I am still pulling 3oz from 6 litre pots and the flowers are better than what I used to manage from HPS.

 

These 2 plants below are the worst looking ones, I have others that don't yellow so much and The New wasn't affected at all, I guess some are more sensitive to light.


Smottie Remixed (such a shame I buggered this beautiful plant up) 

large.P1270327.jpg

 

large.P1270328.jpg

 

Pineapple Skunk

large.P1270330.jpg

 

large.P1270333.jpg

 

This is the Dirty Larry which is looking ok under the 350w

large.P1270321.jpg

 

 

Edited by Smokebelch
9 people like this

Share this post


Link to post

@Smokebelch check out my sweet seeds comp diary ,ive explained a bit about this in there ..@poisonata has mentioned this and i think people glossed over his info .

ive had to dim my scope down from max which just turns everything to crisp right down to under half power and even then i still get a few burnt edges and dropping leaves ,but any lower than that id have to run a heater full time in there 

its mad how little power these can use to grow decent bud .its a headfuck getting used to it .

6 people like this

Share this post


Link to post

Going from seed this time myself have learned really quick not to turn things up too much. Went from 120w to 150w it was enough to purple the underside of some plants and produce rusty spots on another plant. 

 

Need a par meter. :yep:

5 people like this

Share this post


Link to post

Have you checked your humidity. A lack of humidity which goes hand in hand with high temps is the main cause of a Cal/mag problem and sometimes folk think that by raising the lights that is the solution because its lowered the intensity of light. This is true but it also lowers the temps and raises the humidity a tad and this can be the reason a plant picks up

 

Just another angle 

 

Owd 

Edited by Owderb
13 people like this

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now