what is this?! Please need help

Aloha guys I'm a regular grower normally in soil but this season I have gone more secretive and made a micro grow box with a Dwc bubbleponics system inside and so far its been amazing! For lighting I got 4cfl 60wat 120 equivelent 65k bulbs at 1600 lumens each and one t5 120 watt 65k bulb with 2300k and I got 2 more cfl on the side incase my babies need more. But my problem is one of my plants looks to be having a problem and one looks perfectly fine. Do you guys know what this is? And why is only one plant affected in the system and not the other? They are getting fox farm nutes only grow big and big bloom at 1/2 the sceduled amount. Please help I have asked everyone and they all get puzzled so has anyone seen this before or know what this is?? Thank you so much for your time View attachment 3419767 View attachment 3419764 View attachment 3419764 ur timView attachment 3419768View attachment 3419764 View attachment 3419767 View attachment 3419764 View attachment 3419764

First thing coming to mind is algae, check reservoir for white or green slime. I dont think it's pH problems or nutrient burn as plants look fairly healthy. It still would be helpful to have all this info including reservoir water temperature and how frequently do you change water in reservoir.