Hi guys, new to this forum, and have been on a quest to find information on what other people might use in this situation. I had a few grows under my belt before my last few grows in which i switched to using ro water from tap water because i was going to be running a hydroponic setup, so i used it in my last soil grow as well and fought with calcium deficiency for the last 8-9 weeks pretty badly. It took using 2x the normal amount of calmag just to keep them alive and not lose all their leaves. That was in ocean forest which has decent calcium content. That was with fox farm nutrients. I did get them thru to harvest. Long story short on my current hydroponic and coco grows using advanced on the hydroponics, and general hydroponic in coco, i have to use 2-3 or more the cal-mag just to keep them somewhat happy. I switched to tap water in the coco plants and they are incredibly happy with a half dose of calmag, could probably use none in them. For what ever reason this ro water just doesn't work well in the holding and transferring the calcium from the nutrients and cal-mag into the plants. The tap water will work fine in my coco somewhat, it is rather hard at 340ppm so it will eventually cause buildup in the coco, but i switched the reservoir on my drip hydroponic setup to tap water 2 days ago and a very clean nearly spotless reservoir turned into a mess covered with slimy foamy white gunk, just in 2 days. I need to i guess find a product that add's just enough of the minerals back to the ro water to where it works well without adding an eigth of a bottle of cal-mag per reservoir change. Any help on this would be greatly appreciated. About 9 weeks into this grow with a few weeks left to harvest my smaller plants, and 4ish for my bigger ones, and they were taking a lot of leaf damage still with 2x the normal amount of calmag in the reservoir.