Brown Spots

[macnasty]

Hi gang,

I apologize right away for not providing pics, I know they speak a thousand words. I'll try to be as descriptive as possible though. here's the TS form first...

H=Answer if you grow hydro or aero Aerospring
R=Answer if you grow in RockWoolSmall cubes
T=Answer if you grow in HydroTonyes


E-indoor or outdoorindoor
E-Water sourcetap water @ 200ppm @ 500x conversion
E-Source water pH6.8 adjusted to 5.8
E-Age of plant2 plants, 5th week in flower
E-Type of fertilizerGH lucas formula
E-Rate of application (if hydro, this is your PPM number, preferably after each component is added)1100 ppm @ 700 x conversion
E-Lighting source and distance from plantHPS 1000W @ 12 inches
E-Air temperature (both day and night if you are running a dark period)75 day 65 night
HD-Reservoir temperature65 constant
E-Air % Relative humidityaround 30
E-Lighting schedule12/12
E-Type of ventilation your room has6" vortex exhaust w/ passive intake
TR-Did you pre-soak your media in pH corrected solution?yes

I've got 2 plants, about 2-2.5 feet tall each, and they are both exhibiting brown spots on virtually every leaf, both new and old. the leaves themselves look healthy otherwise; dark green, no curling, no damaged tips. except that they all have very dark brown spots located all over the leaves, and each dark spot (about 1-2 mm wide) is surrounded by a yellowish color (about 2-4 mm wide). i've read countless threads but can't seem to target the problem. some of the larger fan leaves are yellowing slightly, but i've read this is the norm for plants 5 weeks into flower. the only additive i use other than the GH flora micro and bloom are very small dosages of grow and 1/4 tsp of koolbloom/gallon of water, as well as .5 ml/litre of AN JumpStart (seaweed extract). one last thing, these brown spots have been around for many weeks, but in the last couple weeks it seems to have spread to the entire plants. Thanks for taking the time to read this, i look forward to your advice. bye.

macnasty Reviewed by macnasty on 12-13-2008. Brown Spots Hi gang, I apologize right away for not providing pics, I know they speak a thousand words. I'll try to be as descriptive as possible though. here's the TS form first... H=Answer if you grow hydro or aero Aerospring R=Answer if you grow in RockWoolSmall cubes T=Answer if you grow in HydroTonyes E-indoor or outdoorindoor Rating: 5

[Rusty Trichome]

1000w at 12" above canopy...? Is that Vortex hooked-up to the hood, or are you running a reflector?
Do you spray anything with the lights still on?
Are you supplimenting with CalMag? (are they getting any calcium?)
Have you changed (increased) your watering schedule?
How do the roots look?

[macnasty]

hey rusty...

1) the fan is not hooked up to a hood. i'm using a reflector.

2) i rarely spray anything on them, but occasionally (less than once a week) i spray a weak solution of AN Jumpstart (seaweed extract) while the lights are on.

3) I'm not using any calmag, or any calcium or magnesium supplement. i thought my tap water would be sufficient.

4) my watering schedule has been consistent since they were young. they are exposed to a continuous spray from the aerospring, 24 hrs a day.

5) the roots are offwhite/cream/yellowish. they look extremely healthy, but i wouldn't know for sure since this is my first grow. some of the roots are almost 1/2 inch thick. the 2 plants share a reservoir which is about 12 inches deep, and the reservoir with the nutes is in an adjacent tub underneath, so that the roots are sitting in a very shallow pool of nutes (1/4 inch) at all times.

p.s. i was thinking about using molasses and/or epson salts.

thanks for the input rusty, your experience is much valued. later.

[Rusty Trichome]

[quote=macnasty]hey rusty...

1) the fan is not hooked up to a hood. i'm using a reflector.
If using a 1000w light, isn't it a bit close, or are you using a dedicated fan to disburse the heat?

2) i rarely spray anything on them, but occasionally (less than once a week) i spray a weak solution of AN Jumpstart (seaweed extract) while the lights are on. I wouldn't spray anything on them until just before lights-out, or raise the hood. If forced to spray with lights on, make sure spray is a fine mist, not droplets, and raisde the lights if possible. Each drop of water is like a mini-magnifying glass on the leaves, which can burn them.

3) I'm not using any calmag, or any calcium or magnesium supplement. i thought my tap water would be sufficient. Could be...was just a thought.

4) my watering schedule has been consistent since they were young. they are exposed to a continuous spray from the aerospring, 24 hrs a day. Not being a hydro guy, I'll leave that one for the pro's, but, 24 hrs a day...isn't that a bit much? I grow in soil, and when my leaves are turning yellow, and greyish-brown blotches appear, it's usually from overwatering too soon after a flush. (beginning of root rot)

5) the roots are offwhite/cream/yellowish. they look extremely healthy, but i wouldn't know for sure since this is my first grow. some of the roots are almost 1/2 inch thick. the 2 plants share a reservoir which is about 12 inches deep, and the reservoir with the nutes is in an adjacent tub underneath, so that the roots are sitting in a very shallow pool of nutes (1/4 inch) at all times. Healthy white growing tips, and no slime. Sounds good to me, but mine are always in soil, lol.


p.s. i was thinking about using molasses and/or epson salts.
If unfamiliar with molasses and the use of epsom salts, would wait. Can do more damage than good, especially if plants are already stressed. A picture would sure help.

[macnasty]

here are some pictures, i hope it makes it easier for someone to diagnose my problem. she still has about 2.5 weeks left in flower, and she is looking real hurt. could someone tell me how this is going to affect the yield? first grow, and i have mixed feelings about this. the last picture is of her newest growth at the bottom of the plant, which looks much healthier than the rest of her. could that mean the problem is fixed? i'm not sure if the damaged leaves are suppose to heal at all.

[seldomBLUE]

That looks like my last girl. Brought a plant in from outside during summer (potter roses) and brought mites in too. I thought it was a serious pH problem when it started. At about 2 wks of flower my soil pH tested high +7 with a 6.4pH H2O flush. Waisted a lot of time doing pH adjustments which were only part of the problem. 4 wks is when i took the photo of the leafs. I didn't see them until i used a micro photo shot at 9 wks. She was mostly dead but she still smoked fairly well. CHECK CHECK and CHECK for mites at the fatest stem area of the under leaf.

[attachment=o212408]

[attachment=o212409]

[attachment=o212410]

[attachment=o212411]

[macnasty]

are those spider webs on that bud? that's incredible, i wasn't even aware spider mites made webs (what do they catch with them?). it can't be mites, because it doesn't explain why the newer growth is damage free. the damaged leaves are gradually looking worse every day. they are hardening and curling. it's not a pretty site

[polishpollack]

I think your light is too close. You could move it up another 12 inches. or even a little more actually.

[Weedhound]

I agree...unless you're running a full on cool tube or some other air cooled enclosed hood 12 inches is WAY too close for a 1kw....I'd go at LEAST two feet and make sure there is an oscillating fan helping to disperse (sp?) the heat.

[Weedhound]

Macnasty.....why are you working with two different conversion rates there?