Brown Spots near the end of the leaves

Hi All,

I don't post much, normally I read and search and answer my own questions. This is my second grow(last one was 7 years ago) and have developed an issue with only one of my White Widows almost 5 weeks into veg. Using a Hydro Drip system watering 15 every 2 hours.

Please look at the pics and let me know what are your thoughts.....especially stinkyattic

My Pics

What is your experience level? Novice

Your Equipment:
.1) Type and wattage of lights. (AgroSun 400 Watt MH
.2) Distance from tops? 6 inches
.3) Reflector type? enclosed reflector with an exhaust fan
.4) Is there a consistent fresh air supply? Yes
.5) Do you have an exhaust fan and a circulation fan? Yes
.6) What are the bulb wattages, kelvin ratings, and schedule? 400W 18/6

Your medium:
.7) Hydro - Hydroton
.8) Size of container. 3.7 gallon / 2.5 gallon reservior
.9) Did you use peat pucks (or similar) to root clones or germinate seedlings? RapidRooter

Your nutrients and water:
10) Source of water? RO - 6
11) Method of checking water ph. Milwaukee SM802 Ph/PPM tester
12) Method of adjusting water ph. phDown Pro
13) Specific brand and N-P-K ratio for each bottle. Following Latewood's legacy nute schedule to the tee
14) How often are you watering between feedings, and how much per watering? Timer 15 minutes every 2 hours. Airstone in each of the reservoirs
15) Any additives or tea's? (CalMag and Liquid Karma with top ups)
16) Are your ph levels stable, or do they fluctuate? Stable at 5.8 to 5.9
17) What is your ingoing water's ph? ...your runoff ph? N/A
18) Do you foliar feed? If so, with what, how often, and at what time do you spray? no

Your growroom:
19) Indoors
20) What size of closet, 3x3x10
21) What are the temps and humidity levels while lights are on? ...With lights off? 79-80 lights on 70 lights out
22) Have you seen signs of insects in the growroom? No

Your strain:
23) What strain are you growing? (1 Indica dominate - 90/10 and 1 white widow)
24) From seeds or clones? seeds
25) Is this an autoflower strain? no

I want to mention that the spots are on random leaves and only on the White Widow. Also over that past few days I noticed a watery like substance on some of the leave. I has no smell and the consistency is a little thicker than water. I have a picture of the spots and the watery stuff.

Let me know what you think.

I'm not sure about the watery substance, but I have a hunch that you might want to play with your calmag addition; if you are doing top-ups only past a week, try a weekly full res dump and change, concentrating on getting that calmag in there first and testing the EC (aim for a ppm of about 250) before adding the other nutes.

Thanks a lot stinkyattic. I was thinking that myself because these girls are drinking quite a bit, almost 5 gallons a week in between reservoir changes. The combined reservoirs only hold 5 gallons. This week I am using liquid karma and RO only for top ups (following Latewood's schedule)and I noticed that the PPM fell from 1500 to under 900 in the 4 days since the reservoir change.

I was worried because I need to flip the lights to 12/12 in a couple days. The tallest plant is now 24" and all 3 are showing me that they are girls.

Hi stinky we missed you

Looks like the plant has stopped complaining. I topped up with RO and CalMag shortly after my original post and the spots have not worsened or spread to any new leaves.

Thanks again for the confirmation stinkyattic

I believe the watery substance is from transpiration. It only happens after a dark cycle and seems to be only where a couple leaves are touching.