4 1/2 week old , nft,rust spots on leaves

Hey guys , just transplanted my clones in a nft system a couple of days ago and during last 2 days I have some fan leaves (mostly the ones in bottom ) having some rust spots, some drying out but the plants themselves look healthy . The ph was 5.9 in one of the tanks and 6.4 in two others ,the feed level was 2.4 (slightly too much ) in all of them . Temperature at lights on 27 -28 Celsius , lights off 18 -20 Celsius . Humidity 20% , solution temperature around 20 Celsius .

So yesterday I changed all the water in tanks with fresh solution with feed levels of 1.6 ,pH 6.0 and solution temperature 20 Celsius . Any ideas what causes this ? I have induced 12/12 cycle and I am using canna a+b flowering nutes. Please guys let me know what you think .

Not much to worry about lets see the whole plant.

So the plants are looking ok, some leaves are still damaged but plants look healthy over all , checked the roots they are nice and white and finally started growing since transplanting in nft .but it looks like the damage is advancing on the leaves it was already present but not showing up on new growth . Temps are a hit high this morning about 28 Celsius and root zone 23 Celsius (I need to figure how to cool the room and water tank a bit better ) but everything else is in check . Any ideas what could cause this ?

That's one of the most damaged leaves I found , maybe that helps out a bit

Looks like burn for me. Let an others guys correct me.

Yeah, I suspect that too , but doesn't burn usually start from tips/edges ? Because this one started from middle of leaf and spread to the edges

Took some photos with HPS off, they are nice and green just those spots on leaves are bugging me out

Your good dude, what you are seeing in my opinion is some cal/mag issue. No yellowing or crispy tips so I doubt its burnt. Everything else looks good. Plus new growth is your guide. It looks good so, I would guess that those bottom leaves are just showing a past issue.

Thanks man , I've been working hard to keep everything in check . How about the purple stems of fan leaves is that a strain thing or some sort of issue ?

Your pics with the hps don't do us any good

I know, that is why I posted two more without hps ,buddy

passitbro said:

Thanks man , I've been working hard to keep everything in check . How about the purple stems of fan leaves is that a strain thing or some sort of issue ?

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Purple stems can and are totally normal. However if the leaf VEINS are red/purple than you have a deficiency but you would also have a bit of yellowing going on with it. My cotton candy Kush chillin dressed in purple stems. Totally health plant BTW.