What is THIS!!! Please Help

Hello Fellow RIO members,
Im on week 3 in flora series
What is this? Looks like it spreading its kinda soft?
Any Idear?

Im pretty sure i started to notice it on the tail end of week 2.



comment if you need more info

is that DWC and what lights do you have. Looks like overwatering (not enough air pumps), res temp to high, or just not enough light.

Looks like classic phos deficiency, brown toward the middle of the leaf. Check your pH.

View attachment 2522530
It kinda like the 2nd phosphorus deficiency on the chart. but my nutis are always 5.8-6.1. They used to be in a DWC system but the roots didnt like it and they were rotting not matter what i did. Also the DWC water got up to 73-75f. They are in the 2 day in a ebb and flow and i bumped them up to week 3. The roots look like a mess and i feel they are going for the worst. I took some clones just in case. The Ebb and flow Temp is staying around 68-70

They are under T5 lighting

Yuh Phosphorus.

So i check my ph 6.0 so idk..
what i can do?
Does it clear up?
What else could cause it, beside ph?

here is some pic of the roots of the 3. They arnt doing well. Moved them in to ebb and flow to help them get more air.

Bumb,
Couple more question
UPDATE.

Its starting to look more yellow?
does that mean its better or worse?