Thats fine you left out the gro to save money flora micro and bloom has everything u need in it and has enough nitrogen u were worried about, and everything else that MICRO GRO contains, that you use it with FLORA BLOOM alone. I looked up that Crysta Geyser water and they seem to filter it correctly leaving the right minerals in the water. If you used that water and then what you said your water should be perfect. If you used ph up or down you coulda used too much of that or the H2O2 is ur issue. That is the only thing i can think of that you did wrong. You said your airstone was bubbling so thats adding oxygen and preventing stagnate water issues, your roots are white, your air temp is right, your humidity is right, your nutrient strength is right, your water temperature is right, your not using tap water so that eliminates all possible hard or soft water issues and contamination issues from that. You cant have excessive calcium or salt buildup in you water because your using spring water and 1/2 nute strength. It has to be that H2O2. I think i thought of everything, anyone else?