Potassium Toxicity?

Hey Roy here,
Im so scared right now! im allmost into week 7 of flowering and I Went to check on my plants and there were looking as good as i could expect from the bottom! But something told me to get the ladder and have a look from above and to me freight i saw these horrible spots and ugly leaves and Some pisstol hairs turning dry? Fist I thought it was some mold or mildew after some googling I figured it might be a Mag toxicity leading into a Potassium toxicity Wich sucks cause i give a shot of P Yesterday and i think thats what made it worst today. I figured i have to flush with a half strenght dose of ferts and wait? hope some one can help
PH - 6.0 ( ran out of calibration solution past 2 waterings been using GH testkit with bluelab pen uncalibrated but still close it just didnt take the ph 4 solution befor i ran out)
EC - 1.5 Putting in…Coming out ?
Water - Hard Tap ( ec 0.5)
Week - 6.5 flowering
Medium - Coco + Perlite (takes like 1gal of water to get run off of 1 plant) help?
Pots - Plastic 7gal (I might be root bounded)
Strain - Zombie Virus Lineage Genetics

Same shit happened to me. Turns out my lights were too close!! How close are your lights

I've seen worse, I think you are feeding a little stronger than I would. I would try 1.0 or 1.2 EC since you are starting with .5 ec water.

Bluepowerade said:

Same shit happened to me. Turns out my lights were too close!! How close are your lights

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like 50-60cm from the plants i had a small lighting issue a while back and raised them ill raise them a bit more. How did your harvest turn out? im still so worried

70's natureboy said:

I've seen worse, I think you are feeding a little stronger than I would. I would try 1.0 or 1.2 EC since you are starting with .5 ec water.

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Yea man I Gave them excess water yesterday to get some runoff and the plant with most issues had an EC of 2.1 iv been wondering how did a 2.1 ec have such a negative effect and after some googling and countless repetition i finally realized ppm dose have 2 convertions ( 4/5 people wont tell you what they are using so u get what happend to me being a ppm of 1500 might be a ec of 1.7 or and ec of 2.0. wich is a drastic difference so this being a heavy feeding indica ? I figured i was being moderate with the ferts watching vids and reading up but still got screwed with the ppm ec conversions (nothing to do with equipment just the know how).

.Smoke said:

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thanks man iv been watching these graphs and pics for weeks just needed a second opinion its my first solo grow ever and im glad i could identify the problem so quick. Ill be doing a flush in a bit and hope im still good when harvest comes.

thanks again guys