Looks like overwatering to me as well. Lift the pot, if shes got weight to her then don't water. Some people say to not use the finger method, but if you're not great at the weight guessing then use it. Stick your finger in the dirt midway between the stalk and the edge of the bucket in 2 or 3 spots (I use my pinky) about an inch, or, to the halfway point between your first and second knuckle. If you pull out your finger out clean she might need water. I just wait until I notice the bottom leaves starting to droop. Then water when the light comes on.
With a pot that size vs the size of your pot, I would be using
foxfarm at 2.5 mLs a gallon,
cal-mag at 5 mLs a gallon (I have R/O water that gets deionized so I use more
cal-mag). Do a half gallon on each plant, give 10 minutes. Then hit her with another half gallon. For now I would let them fully dry out. To the point where you notice a slight droop. Then water. If your using crappy soil then you will need nutes. High quality soil tends to run hot and nutes won't be needed. If you're using tap water then
cal-mag should be ok.... R/O water will need
cal-mag as the R/O filter removes calcium and magnesium.
The amount of nutes your plant needs is directly related to the DLI (daily light intake) your plant is receiving. Light manufactures list Ppdf and PPF, which are great to see how much of an area a light can handle and the density of the photons. But DLI is the bottom line Stat that a plant survives on. The higher the DLI, the more nutes it needs to build its cells, the more water, it drinks to bring in the nutes. So never skimp on the light. That's really the backbone of any grow. Then build out from that..... Think of the light as a racecar motor. The nutes are the tires. As you improve your motor you have to get better tires or you hit the wall. I could go on for hours..... Sorry, hope that helps? That's my 2 cen.....er... 75 cents lol.