Grow Mediums red poision sick...pls pros. take a look.

[passionatefarmer]

This was today. Added 1 ml per gal of cal mag and this was reading. It was about 600 but I dropped it some with fresh ph water.

 

[passionatefarmer]

The purp color Is one pheno of the red poision auto from sweet seeds.

 

[jackmc]

I had the same problem. My lower leaves began to turn yellow between the veins. I was running ppm at 300 and my ph was a little high. I went full strength Magical (Cal/Mag) and corrected the ph and the plants took off again.