I always ph to 6.5, checked closely for critters there are none. The only change I have made is my water, in the past I have used lake water from behind my house, the lake was sprayed with an herbicide to kill some lily pads so I stopped using water from the lake and have been using purchased purified spring water. I started adding cal-mag plus with the change in water thinking it would need the extra. I was thinking maybe I was still deficient on something. Should I flush it good and try just minimal nutrients? I use advanced nutrients, micro, grow and bloom. Any other suggestions are welcomed.