~21 days into Mataro Blue Auto-Flower + Non auto yellowing questions

Hello everyone, my first post here on these forums to show some friends. Three of these are Kannabia Mataro Blue auto's and one is a non-auto feminized green love potion. It's been roughly 3 weeks since transplated from cubes into FF Happy Frog receiving only 6.5-.7 PH water, no nutrients added yet, and temps stay in the mid 70s. The light cycle is 18-6 right now and the non-auto potion seems to love it! I have heard with Mataro Blue that it isn't a fully "stable" strain yet, so I will have to switch to 12/12 to really induce bud production. Recently, I have started to notice a bit of yellowing on some of the bottom fan leaves across all plants except maybe one, a bit medicated at the moment. Curious to see if anyone can chime in and provide some insight as to what this problem may be. Did water just get on leaves during feeding resulting in burnt spots? To high PPM water? MG deficiency (roots show NO sign of purpling or throughout any of the veins in the leaves). Help me out friends here at RoI! (Please bear in mind these will be entering a cabinet outside of the closet that's mylar coated with passive ventilation, just waiting on fan and carbon filter to arrive - temps stay too high without my suction!)

Here are some crappy iPhone pictures I snagged tonight. First time using the websites uploader so not sure how it will work! The picture will all four of them goes as followed: Back left - Mataro. Back right - Mataro. Front right - Mataro. and Front left - non-auto green love potion (it started 4-7 days after the Mataro's).

Thanks, and hopefully everything uploaded as intended and you can see the "burnish yellow" marks I am talking about! Oh, and the nug porn is purple kush on left and boston bling on right.

nonuggets said:

they look super green...i'd say try flushing them and cut back on the nutes

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If you read, I am not giving them any nutes. Thank you for the reply, however I am looking for someone who will answer my questions not just look at pictures.

No one to chime in?

Looks like splash burns to me. You can trim off a few of the bottom fan leaves so you can get under her to water better. Also if you foliar feed make sure to let them dry out before putting back under light or they can burn.

what are your temps looks high in pic 3 with the top leaves starting to canoe

D3monic said:

Looks like splash burns to me. You can trim off a few of the bottom fan leaves so you can get under her to water better. Also if you foliar feed make sure to let them dry out before putting back under light or they can burn.

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No foliar feeding here. The plant(s) are at another location and are sometimes watered by someone else, so that's why I thought it could be burnt. Thanks for chiming in!

grorite said:

what are your temps looks high in pic 3 with the top leaves starting to canoe

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In the original post it says the temperatures stay in the mid 70's, the highest that closest has ever seen is 85 degrees. It's in the ~30s-50s (Fahrenheit) outside and the house stays warm in the 70s. We let the temperatures actually drop lower at night as I have read that this strain will start to produce a bluish hue bud, and some of the fan leaves are starting the show it. I do see what you mean about the "canoeing," though.

Looking to get a couple more answers on this so I know I have no issues and they are indeed just burn marks!