CalMag....yes....right from the start... My hydro guy is very strong on 50% of the main nutes being CalMag and using RO water (my hydro guy walks on water btw) then the rest in bloom nutes then supplements. It's always worked well for me.

Sounds like your ph is fine.....seriously if it's at 5.8 vs 6.0 during bloom or day 6 or whatever dont' stress.....it doesn't have to be perfect. If you have your ph between 5.6-6.0 I think you're good....that's my rule anyway and again...never had issues.

Maybe just not enough CalMag? Or perhaps too much of something else (at 1700) that would cause the plant not to uptake a certain nutrient etc....everything interacts. (I say that like I know what I'm talking about but I don't really....I read it somewhere )

Good luck
Weedhound Reviewed by Weedhound on . 5 gal DWC Flowering - advice / formula needed I'm flowering two plants, usings 5 gal dwc buckets. Right now all I'm using is: Hesi Bloom - 60 ml cal-mag+ 25 ml liquid karma, 30 ml Hesi super vit 5 drops the ppm turned out pretty high (I was just going by the dosage on the bottle) I think it was around 1700 so I deluted with more water and brought below 1500. I'm using six 42 watt warm CFLs, two 30 watts and they seem to be slightly cooler cfls, and 4 6500k 26w cfls. Rating: 5