Can't identify young plant problems ... HELP

The pictures attached are of two different plants. Same strain. Soil is light warrior. Water is distilled. Light is a 400w placed about 11in-12in away. One plant is showing a small amount of discoloration and small amount of curling. The other just discoloration. I have other plants of the same strain that are perfect. What should I do?

Are you adding cal/mag to your distilled water?

Bugeye said:

Are you adding cal/mag to your distilled water?

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No. I thought it could be that or a nitrogen def

Calcium is vital for nutrient transport so I would start by getting some liquid cal/mag and adding it to your water before you do anything with nitrogen.

Bugeye said:

Calcium is vital for nutrient transport so I would start by getting some liquid cal/mag and adding it to your water before you do anything with nitrogen.

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Thanks a lot. I'm going to need a meter right?

A TDS or EC meter? A water meter? A ph meter? Yes, yes, yes! I have multiples of each and rarely use them but when I have an issue they all come out.

Bugeye said:

A TDS or EC meter? A water meter? A ph meter? Yes, yes, yes! I have multiples of each and rarely use them but when I have an issue they all come out.

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What are the tds and ex meters for?

kushgro said:

What are the tds and ex meters for?

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measuring ppm on nutrient solutions or source water.