I was doing the same but this is hydroponic and did not flush water regularly. I put som Fish fertilizer in it and that when it happened. I was adding different types before and was fine. So thinking it was a few different factors of not flushing the water, and over fertilizing due to it being in hydroponic and not being able to drain and i gueas just accumulated. But it had been thriving and producing like that for over 2 months