Flood table advice

So this is my first attempt at a flood and drain table, I have the girls in clay pebbles in 5 gal smart pots.. it floods every 4 hours for a total of 15 minutes and only turns on when the lights are on (was told not to feed them when the lights are off) the ph was a bit high at 6.5 the rpm of my neuts is around 550 and I'm running remo nutrient.

My brother set this up, I usually do DWC and never have any issues. I think there needing more water cuz they clay doesn't hold moisture... but I need some advice.. anyone? I know the last picture you cant make a good diagnosis cuz the lighting but it's all I had for pictures.

If you don't get the dust washed off the pellets REALLY well then it causes the pH to rise. If you do a really good job of rinsing them then after a day or two the pH is stable, before that it tries to rise a couple points each day IME, requiring a little adjustment. Fix the pH problem and your plants will look better.

The wilted plant is probably not planted deep enough to get the roots wet and would require top watering until the roots are down below the water level.