What wrong with my leaves?

[Ozma9683]

The nasturtiums are variegated.
Other than that, the Cauliflower leaves, and kale leaves potentially showing chlorosis.
Not sure what caused it but new growth seem much better.
I have some issues with cucumber leaves browning on tips.

Biggest issues is determining appropriate EC or PPM.
This is because my system contains, lettuces (Lower ppm) and tomatoes, cuces, zucchini etc (Higher ppm)

Adjusted today from EC-2.0 (1,000 ppm) to (900 ppm)

Maybe a low nutrient solution content will help with brown tips and chlorosis?