Doc you are correct about the RO system that adds minerals. I own one and had some problems growing black water using that unit. I'm currently growing 1 more round with black water and using just RO water no minerals and this round is looking great. Just thought i should share that with ya. HB...
Thanks doc i was hoping not because i have some landrace black afgan, purple nepalese coming and i want to use that for my second run. I need to order some second run amendment.