[GpsFrontier]

Hello daytonajim00,
I can see a few possible issues. But first you say you flood the system 4 times a day, but didn't say for how long. It's not how many times you water them, it's the total amount of time the roots are completely submerged that would suffocate them withough't enough dissolved oxygen and air bubbles. You can water 15 times a day with no problems depending on the type of growing media, and as long as the roots aren't submerged too long each time.

With that said, it's likely the plants can be suffering from stem rot. Stem rot and root rot are different. From the pictures it looks like the roockwool cubes are saturated with moisture. The rockwool cubes hold much more moisture than the rocks, and the rockwool cubes touch the base of the plant stems. Constant moisture on the stems can easily lead to stem rot. That's why you want your water level in the system to be about two inches below the top of the growing media. You want the root ball to get moisture, but you want the top of the growing media to be dry.

Another possible contributing issue is the light source. While the leaves look like they have good shape and color. Plants often have skinny elongated stems and leaves as they try and reach as high as they can, as quickly as they can to reach up to the light source when using florescent lighting. Long skinny stems simply can't support the weight of the plant as they get bigger. Florescent lighting is a low intensity light source and really works best for low light requirement plants.

Third problem I see doesn't have anything to do with your post, but I was wondering if you had a plan of what your going to do when those plants get bigger? One broccoli plant can easily grow 4 feet wide as well as tall. If you try to transplant them into another system, how do you plan to do that without tearing and damaging the roots?