(Pics) plants suddenly have discoloring.

[420Rick]

1st 2 pics are of healthiest plant which is a nice green color but today had a couple of yellow spots and a few fan leaves looks like someone sprinkled some rust on them. 3rd pic is of plant that is turning yellow thruout but the veins in the leaves are still dark green. All are fed spring water with a very slight amount of nutes when pot is dry. Indoor, temp at 75-85f thruout day and night, mars sp150 light along with a flowering light turned down to minimal output, plenty of airflow. Help

[Canuck147]

Need to know what your pH in your water is - calcium/magnesium deficiency is my guess. Needs a calmag supplement.

Or worse - if your pH is suspect then it could be nutrient lockout.

Should be a more vibrant green. Darker in color.

[alltatup]

Agreed. I bet it's lockout. READ THIS: https://www.growweedeasy.com/flushing-sick-cannabis

[420Rick]

Runoff tested roughly 6.5 but plants were already back to lo ok king good. Once I add nutes to my water the water ph drops to 4.5, should I adjust before feeding the nute water?

[vostok]

nute burn with a need for calmag

miss a few feeds maybe a flush

last flush add calmag

good luck