tiny rust coloured spots peppering 2 main fan leaves.

Hi all, thanks for reading. Here are the details and pics:

Problem: Tiny rust coloured spots peppering 2 main fan leaves, the rest of the plant looks fairly good.

Growing indoor, under 130W 2700K CFL, with carbon filter and extractor fan.
Temps have been a bit hot recently, never gets over 30 degrees however often sitting around 24-28
Watering twice a week, last bloom nutes given about a week ago. Was thirsty yesterday so gave a bit of tap water as usual (very gd quality tap water here).
Growing Medium is top quality potting mix.
Stage of growth is day 45- mid bloom for an auto-assassin autoflower that normally harvests around d60
Here she is:


Any comments appreciated, very grateful for any input . I am just so worried about my little girl, I hope she is gonna be ok! She was due for another feed tonight and now I dont know if I should go ahead!

hey mate,

check out this thread

https://www.icmag.com/ic/showthread.php?t=11688

from a quick glance through there it looks like it maybe a calcium deficiency

ps. I think it may be cal mag deficiency but would really like another opinion.

pH?

............

Thanks, guys, I am putting it down to calcium deficiency... I wasn't supplementing calcium at all. Just added some cal mag to the nute feed (extra diluted this time) and fingers crossed it doesn't get any worse!

StealthAssassin said:

Thanks, guys, I am putting it down to calcium deficiency... I wasn't supplementing calcium at all. Just added some cal mag to the nute feed (extra diluted this time) and fingers crossed it doesn't get any worse!

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What is your pH. You shouldn't need to supplement calcium with a good fertilizer.

are you sure you don't have thrips or mites? looked under the leaves?

Look for mites under leaves..if clear calcium because lack of or pH.

Yea, I would go a calcium /ph problem. If I understand correctly though, cal problems resolve slowly when treated ?

that looks to me like spider mites doin their thing..they just havent spun webs yet. LOOK UNDER THE LEAVES!!!

Mites like a mother fucker! Been there

That is a bug problem!

Calcium deficiency. The age of the plant combined with the pic makes this easier. The pics do not show typical spider mite damage as much as an evolving Ca deficiency although checking for those little bastards is a daily job. With calcium deficiency comes magnesium deficiency as they go together, hence the combination adds for them. Do not lower your water pH at this age as cal/mag uptake require the pH to be a bit higher than during veg at around 5.9 - 6.1 at the root zone.

But please check your leaves' undersides and let us know since many here are so positive it is mite damage.

hotrodharley said:

Calcium deficiency. The age of the plant combined with the pic makes this easier. The pics do not show typical spider mite damage as much as an evolving Ca deficiency although checking for those little bastards is a daily job. With calcium deficiency comes magnesium deficiency as they go together, hence the combination adds for them. Do not lower your water pH at this age as cal/mag uptake require the pH to be a bit higher than during veg at around 5.9 - 6.1 at the root zone.

But please check your leaves' undersides and let us know since many here are so positive it is mite damage.

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His plants look okay in the pic, but that's mites problem. I'm still dealing with my mites too, my self in flower

EvlMunkee said:

are you sure you don't have thrips or mites? looked under the leaves?

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I'm siding with evlmunkee, doesn't look like a cal\mg def, my experience rust looking spots tend to indicate this. Yours looks like something eating the chlorophyll out of the plant. It's an infestation IMHO, thrips most likely since it appears no webbing of spider mites can be seen and thrips are really hard to see but not as hard as spider mite. Spider mites leave piercing holes in your leaves, do you have tiny holes in them?

DANKSWAG said:

I'm siding with evlmunkee, doesn't look like a cal\mg def, my experience rust looking spots tend to indicate this. Yours looks like something eating the chlorophyll out of the plant. It's an infestation IMHO, thrips most likely since it appears no webbing of spider mites can be seen and thrips are really hard to see.

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If it is thrips apply some neem oil or liquid lady bug and hope that is all you have, spider mites are tough little bastards. No pest strips plus neem oil raise humidity if possible and use Safer Insecticidal Soap with some tobacco juice and chili pepper powder added.

DANKSWAG said:

If it is thrips apply some neem oil or liquid lady bug and hope that is all you have, spider mites are tough little bastards. No pest strips plus neem oil raise humidity if possible and use Safer Insecticidal Soap with some tobacco juice and chili pepper powder added.

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Just out of curiosity what brand of soil did you use, mites can be found in cheap non sterilized soil. They can come from other sources, bringing plants inside from outside. Pets who go outside come inside near your plants? Received an infected plant from another grower?

a cal-mag is easy to spot .......... thats how i remember it rust colored spots means it needs cal if its praying then its mag

Spider mites, most definitely. Spray with azamax, neem oil with plain detergent, or avid for high strength pesticide. Avid will store toxins in plants leaves, dont spray for at least a month before harvest.

I had a mite problem and I battled the little bastards for months until I bought a pump sprayer. I mix a teaspoon of neem oil and a drop or 2 of dawn dish soap to a gallon of water and the plants got soaked twice a week for a few weeks and it took care of my problems. I spray every now and then just for maintenance. Make sure you have good air flow when you do it. Good luck!