"Rust" on some leaves

Hi.

I noticed that some of my plants having like rust stains on bigger leaves(photos attached)
Im new in indoor growing and I dont know what it is. Maybe overfeeding or some kind of deficiency?
They are in soil, but in very small pots{2.5l), Hesi soil nutrients, Migro led lights.
They are in 4.5 weeks in 12/12 mode.
I use dripping system for watering and feeding. I feed them at begining if day cycle.
Mostly I prepare my nutrient coctail and mix it with water and this is used every day at the plants morning.
I noticed this "rust" on three of seven plants.
I will ad some mote photos soon as possible.
Can you please help me?

Let me get some more informations about my grow place:

It is a small closet grow, 60x105cm, with two Migro 100 led lights.
Max day time temp inside grow place is around 26°C , nigt temp could go low to cca 15°C. I have two 16cm Secred Jardin fans in closet and one much stronger temperature controlled fan for sucking the air out of closet.
Grow medium is soil mixed with perlite named Canna terra professional. Like I said before, I have 6 very small 2.5l pots and one bigger Airrap 8l pot. In small pots are Royal cookies, Royal gorilla, Royal domina, Critical, Skunk xl and I.C.E. all fom Royal Queen Seeds and in 8l Airrap pot is Unlimited from Bulk seed bank. All plants are from feminized seeds and are from 30-50cm high. Because I have so small pots I am watering them with nutrients daily.
I mix nutrients (Hesi Phosphorus, Hesi Bloom complex, Hesi Boost, Hesi Hesi PowerZyme, HesiSupervit and CarboLoad) in around 70% of manufacturer recommended strenght. For watering/fertilizing I use this Auto irrigation drip system. Feeding is right at the beggining on the day cycle (flowering 12/12)

This new brown spots or stains are on Domina, ICE and on SkunkXL for now. Other four plants are ok so far.
I added some CalMag in my liquid container, and i use some of it for foliar spraying. Now Im waiting for some result, maybe...
Some of plants are begginig to get purple tan, but Im not sure that is in relation with my problem, because the Gorilla and Cookies are also getting some purple colour, but have no brown spots.

It could also be manganese defficiency?

looks like a calcium deficiency that's slowly getting worse.
what are you ph'ing your water at? too low ph is one cause of calcium problems.
i'd keep adding a small amount of cal mag with each feeding. don't go crazy, more, very often, is NOT better.
next time, add a little dolomite lime to your soil before you plant. you still have to add cal mag for the first couple of weeks till the lime starts to break down, but then it should carry you through the rest of the grow

Thank you Roger., i will dou like you said.

Are chicken egg shells also ok?
I was thinking if would I boil shells, dry them and crush them to dust and then use this as additive for calcium...

I edited and added some more pics in my second post.
Ph of my nutrients/water mix is around 6.5.

I feel like the rust on leaves is a phosphorus deficiency look on google for that go to images. I also have read that when temps get down to 15 the plant has trouble using the phosphorus even if it's there.

Yes, it might also looks like phosphorus defficiency, yes. I will take some better look, when the lights comes on.
I will add some more phosphorus in the water tank and maybe some more with foliar feed, ill see at the evening, when I can come to my plants.
Or, I will wait for a day or two to see if the CalMag gives some improvment, which I aded yesterday.

I guess that the already damaged leaves does not gets like new again, even when deficiency is gone?

It is not every night 15°C, but only when is wery cold outside. Usually is more 16 degrees than 15.

Why are you watering everyday?You need to let them dry out between watering.

True enough yea i would wait to see if calmag works. Before you ad anything else. But I read a few temp changes like that can make it hard for plant to get phosphorus also if your your using hard water the salts can build up on roots and make it hard for nutrients to get used even if there is lots avail.

nmibud said:

Why are you watering everyday?You need to let them dry out between watering.

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Because they grow in such small pots and they have no acumulation. I think and it looks like they get dryed between watering cycles. It is also not so big quantities of liquid. As far I did some experiments, I gave to all seven plants around 2 or maybe at most 2.5l daily.
Im afraid to get the soil too wet, because I had some serious troubles with fungus gnats earlier at start of 12/12 floweing cycle...Now gnats are gone.
Is possible to get those leaf rust from owerwatering?

Loudigity said:

True enough yea i would wait to see if calmag works. Before you ad anything else. But I read a few temp changes like that can make it hard for plant to get phosphorus also if your your using hard water the salts can build up on roots and make it hard for nutrients to get used even if there is lots avail.

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Well, I use drinking water from the pipe, which could be hard, but I don't know how hard it is.
I only lower ph from original cca 7.5 to ph 6.5.in final stage before goes to water tank.
I mean, I mix water and nutrients and then I do some ph correction, if needed.

Plants watered too often will be sickly and yellow.Larger pots work better,I like the fabric ones.

Penivc said:

Because they grow in such small pots and they have no acumulation. I think and it looks like they get dryed between watering cycles. It is also not so big quantities of liquid. As far I did some experiments, I gave to all seven plants around 2 or maybe at most 2.5l daily.
Im afraid to get the soil to wet, because I had some serious troubles with fungus gnats earlier at start of 12/12 floweing cycle...
Is possible to get those leaf rust from owerwatering?

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Leaf rust is a big incmdick

Penivc said:

Well, I use drinking water from the pipe, which could be hard, but I don't know how hard it is.
I only lower ph from original cca 7.5 to ph 6.5.in final stage before goes to water tank.
I mean, I mix water and nutrients and then I do some ph correction, if needed.

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From everything.i have read a clean water source is a really.big factor for healthy plants like rain water or reverse osmosis atleast if your using tap you should try to get the chlorine out if you leave the water to air out or put a pump in like you would use to brew a tea to get chlorine out faster but r/o water is the way to go it's pretty cheap big 18L water jug is 11 bucks then 4 to fill each time or you can get a reverse osmosis filter they run anywhere from 150 to 700 I have seen

Loudigity said:

Leaf rust is a big incmdick

From everything.i have read a clean water source is a really.big factor for healthy plants like rain water or reverse osmosis atleast if your using tap you should try to get the chlorine out if you leave the water to air out or put a pump in like you would use to brew a tea to get chlorine out faster but r/o water is the way to go it's pretty cheap big 18L water jug is 11 bucks then 4 to fill each time or you can get a reverse osmosis filter they run anywhere from 150 to 700 I have seen

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If use hard water for so long you see on your tap heads or in you kettle it get all that build up that with happen to your roots eventually and make nutrient lock outs

nmibud said:

Plants watered too often will be sickly and yellow.Larger pots work better,I like the fabric ones.

Click to expand...

Thanks. I did used this small pots just for this round. For next grow round I have six or eight 8l Airraps. I used this mini pods just for searching for my personal best strain. I had so low ceiling and I was afraid the plants in bigger pots will get too big and they could reach too close to my lamps.
Now I have little more height space, so I can afford little bigger Girls..
Do you think 2.5l daily is too much for so small plants like they are now?

Penivc said:

Thanks. I did used this small pots just for this round. For next grow round I have six or eight 8l Airraps. I used this mini pods just for searching for my personal best strain. I had so low ceiling and I was afraid the plants in bigger pots will get too big and they could reach too close to my lamps.
Now I have little more height space, so I can afford little bigger Girls..
Do you think 2.5l daily is too much for so small plants like they are now?

Click to expand...

I feel like if you water that much each day your literally flushing all the nutes out I could be wrong though just a thought. If you dont have lots if height do some low stress training it works awsome!

Loudigity said:

Leaf rust is a big incmdick

From everything.i have read a clean water source is a really.big factor for healthy plants like rain water or reverse osmosis atleast if your using tap you should try to get the chlorine out if you leave the water to air out or put a pump in like you would use to brew a tea to get chlorine out faster but r/o water is the way to go it's pretty cheap big 18L water jug is 11 bucks then 4 to fill each time or you can get a reverse osmosis filter they run anywhere from 150 to 700 I have seen

Click to expand...

Sorry, English is not native and I got stuck sometimes... what is incmdick ?

About our tap water, we have no chlorine ar any other artifical additive in it, Im sure fir that. It is only pure water, but it looks like it is hard, yes.
Is RO only way to soften water?

Loudigity said:

I feel like if you water that much each day your literally flushing all the nutes out I could be wrong though just a thought. If you dont have lots if height do some low stress training it works awsome!

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But water never comes out thru drain holes on the bottom, is this still flushing? And they also get new nutes with every watering... Im just thinking loud

Penivc said:

Sorry, English is not native and I got stuck sometimes... what is incmdick ?

About our tap water, we have no chlorine ar any other artifical additive in it. Me and my three neighbours have our own water reservoir for our few houses and I can be sure there are no additives like chlorine in it. It is only pure mountain water, but it looks like it is hard. I live in pretty much unpolluted country land.
Is RO only way to soften water?

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I dont know to tell you truth about softening and I didnt mean to send that other jibberish lolol I read a book True Living Organics I highly reccomend it if your growing organically.

I will try to get this book and read it, thank you.

Is possible that brown spots are wind burn?
I have two small vents in this small space and those two most affected plants are right in the middle of a strongest air flow...

Penivc said:

I will try to get this book and read it, thank you.

Is possible that brown spots are wind burn?
I have two small vents in this small space and those two most affected plants are right in the middle of a strongest air flow...

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The brown spots shouldnt be from wind google it and check it out. Www.growweedeasy.com is a awsome website for everything diagnosing any kind of problem on your leaf. It will literally t