Is that kelp a liquid or more like a powder?
My job here is to help new growers like yourself. I only wish you had come here before you started so we could have helped you get off to a better start with the right soil and nutrients. If you would, give me a list of all the nutrients you have and their NPK values. Let's see if we can't figure out a feeding schedule for you. In the mean time, let those pots dry out well, till they are very light when you pick them up, then give them plain water again. Then we'll see about starting to give them some nutes.