What's going on with my leaves? Light Burn?

I’m on day 35 of flower. I switched my main light to a DIY bridgelux LED on Saturday. The light is on a dimmer and I have it set pretty low because after the first day the leaves started changing color. The tips started to get dry looking and some started turning a black or purple color. I’ve got pictures below. These could be a strain that turns purple. The person that I got the seeds from got them mixed up, but one of the mother plants was purple. Could that be what I’m seeing with the darkening of the leaves? Does any of this look like light burn?


I noticed that it’s only on the larger fan leaves. Are they just being phased out, and need to be trimmed off?

Are you talking about that purple in? Cause that looks more like genetics. Congrats… she’s turning purple and not because your lights. Looking good


Well that’s good to know. I was also concerned about a lot of the tips drying out on the larger fan leaves. I decided to trim them all off since all of the sugar leaves look good. Besides looking cool, is there anything about people plants that makes them more desirable?


A support ticket will help us help you. Can you please fill out a support ticket? Please include what type of water you are using.

COPY/PASTE the below list into your forum post.

Answer these simple questions the best you can.

If you do not know, or do not use something; Just say so; Or post

NA (non-applicable)

• What strain, Seed bank, or bag seed

• Method: Soil w/salt, Organic soil, Hydroponics, Aquaponics, KNF

Soil brand and type

• Vessels: Pots, Grow beds, Buckets, Troths

• PH of Water, Solution, runoff (if Applicable)

• PPM/TDS or EC of nutrient solution if applicable

• Indoor or Outdoor

• Light system

• Temps; Day, Night

• Humidity; Day, Night

• Ventilation system; Yes, No, Size

• AC, Humidifier, De-humidifier,

• Co2; Yes, No

If growing Hydro some additional questions:

-DWC? RDWC? Autopots? Ebb and Flow? Other?
-Distance of liquid below net pot (DWC)
-Temperature of reservoir
-TDS of nutrient solution
-Amount of air to solution

Always try to upload a clear picture of any issues you may have to allow the community to assist you. Pictures taken under natural or white lighting are by far the best.

Add anything else you feel would help us give you a most informed answer should be included. Feel free to elaborate, but short and to the point questions and facts will help us help you in a more efficient manner.

Here is my ticket @MidwestGuy

• What strain, Seed bank, or bag seed - Unsure, but 50% chance that it is a purple colored strain.

• Method: Happy Frog Soil

• Vessels: 5gal Fabric Pot

• PH of Water, Solution, runoff (if Applicable) - 6.2-6.6

• PPM/TDS or EC of nutrient solution if applicable - N/A

• Indoor

• Light system - Two 100W LED Garage Bay Lights - 12000LM/6500K each. On Saturday I added DIY LED with 8 Bridgelux
BXEB-L0560Z-30E2000-C-B3 strips
on a 1050mA Meanwell HLG-240 Driver with dimmer.

• Temps; Day - 75-80°F / Night - 68-73°F

• Humidity; 60-65%RH Day & Night

• Ventilation system; Yes, 4" 195CFM Fan with carbon filter on the outlet

• AC, Humidifier, De-humidifier - A/C in house Dehumidifier in room with grow tent.

• Co2; No


  • Water Frequency is about 3-5 days alternating between water only and feed.

  • When using water only, I have been using DI water pH= 6.2-6.8 Conductivity ~ 2uS/cm

  • When feeding, I use tap water that has sat out for at least 24hrs. Our tap water is hard so there should be plenty of Ca & Mg in it. Nutes are Fox Farm 2-3tsp/gal Tiger Bloom and 1 tsp Grow Big per gallon. I feed with 1 gal of water.

But it kinda looks like both symptoms of each of these nutrient deficiencies :thinking:

That all looks reasonable. The burned leaf tips make me suspect a bit of nute burn, but if your EC is 2.0 now I would keep it there and not worry about it. I don’t see any symptoms of light burn and the height of the light is okay.

Purple stems is normal and nothing to worry about. Some strains and environmental conditions can cause even the flowers to appear purple.


Maybe I should switch back to tap water for my non-feed water seasons. I switch to DI water a few weeks ago.

Conductivity of my tap water before adding nutes is around 700. Would that change your thoughts?

That is very high. I would use distilled or RO water.

If you want an input PPM of 1,000, then (with your tap being 700,) then you should have a solution that measures 1,700 PPM as a simple example. Distilled or RO water will have a PPM less than 10.

Have you checked the calibration of your PPM meter? 700 is really high.


Yeah part of my job is water treatment so I’m confident in those numbers. I just double checked and my DI water is actually 0.3uS. The high conductivity of my tap water is why I started using DI water between feeds. The tap is 700 uS/cm not ppm.

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Midwestguy has ya covered and will get ya back on track better than I can :sunglasses::facepunch:t2:

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My 2 cents… I have really high tds in my tap water to, in hopes to avoid any deficiencies I use a 50/50 blend of tap and ro water which brings my ppm to 300ish from nearly 600… just an idea :bulb::wink:

That seems similar to what I do since I alternate between tap and DI water. Your method might be a better way to make sure I don’t give too much micro nutes.


:arrow_up:Super good advice on tweakin inputs to plants…I’m diggin the collaboration goin on here not gonna lie…if I ever grew indoors I’d grow like sooo many people on here y’all are awesome


I run the tap water through a couple 10x2.5 filters with coco charcoal and add I little pinch of vitamin C to lower the ph just a bit, I grow in living soil so ph isn’t that much of a big deal to me but the vitamin C doesn’t affect my soil in anyway I’m aware of and the ph of 7.6 I just feel better bringing it down to 6.8… old habits I think more than anything

I am by no means a pro, but this is high even for human consumption. Not ridiculously, but every chart I’ve seen for normal water has anything over 500 as a red zone. I only post because it could be cause for concern. Again, I’m no pro, so I could be wrong. Good luck with everything

@MidwestGuy has you covered on the leaf color. I get that on several different strains and like it. I run cooler temps to bring they’re natural color out. Northern Lights about a week out from Harvest :love_you_gesture:

Just saw this part so disregard last post