hi there homeboy, first off, daym ! best description i've seen in time out here bro, seriously top marks. You're killing it in every respect. Second : tap water - how are you gonna trust the authorities to tell you what s in your water, same people putting chlorine in there right? That's actually the main problem with tap water : it's got a bunch of chemicals in there that will eventually lead to issues in your plants if you're not careful. So if you're using tap water you can do two things to avoid "cross contamination" or "inter-chemical" lock outs - these are not technical terms by the way, just how i think lol. Take tap water and leave it out for 2 hours or over night - should let the chlorine evaporate. Or use two tablespoons of the cheapest active carbon you can find and just add it to the water, give it a stir, wait an hour. this will remove the chems that might prevent uptake. When you add Cal Mag suplements, again you're correct - can't really be too much, the saturation dose will be indicated on the bottle, and every one of those cal mags are a bit different. One thing they wont tell you is that there is actually plenty of N in those things, so balance that out accordingly. finally a little known fact is that Ca uptake from the roots is efficient at like 20% not much more. Ca uptake by the leaves is 95% so almost perfect. The quickest way to fix the deficiency is to use a foliar spray - just be careful not getting the juice on the buds when you do it - maybe use plastic film to protect the buds. i think the max does for cal mag in the water is like 64 Mg/l but dont quote me on that, that might be the max dose you need for the spray, and I cant find my source again.... hope this helps bro ! π