Using RO water and adding
cal-mag. Cutting edge nutrients. Does the micro have enough secondary nutes to not need the cal mag? Getting yellow leaf veins in new growth. Which would be
cal-mag deficiency? Once I add
cal-mag it really jumps my EC up to where I can only add small amount of nutes. Is there a ratio anyone knows? I know RDWC uses less nutes. Anyone have some advise. Just scrapping second run of autos due to stunted growth and the yellowing leaf veins.
I don't use Cutting Edge, but I can comment a little. I run several RDWC systems.
First, RDWC does not use less nutes - in fact overall if you have your system tuned for growing trees, it uses more. It's just that the TDS / EC needs to be lower because they are so available for take up. Easy to burn the plants if you have too high a concentration, you just have to add smaller amounts more often to keep it in the sweet spot.
I also don't run autos because I want complete control over the entire plant - root ball size, veg time, etc. I'm sure you understand. For me, a properly tuned RDWC setup is like a Ferrari if you are doing it right, or it can be a demo derby car if not. It kinda just magnifies things both good and bad. Experience lets you tune for the good and eliminate the bad (to a point). But changes happen quickly and with little inputs - so you can easily overcorrect and be your own worst enemy.
In terms of EC values and
Cal-Mag - totally depends on the timing and stage of the plant at least with Photos. I'm not sure my EC numbers or techniques apply to you since you have different nutes and are running autos, but I'll help where I can. Maybe post a pic and we can diagnose together?
Here is a generalization that I think will hold true for both of us - Cal Mag is an important amendment early in the plant life, especially with RO as your source. Maybe a rule of thumb I work with: starting with 0 PPM RO water, add Cal Mag to get to 125 - 150 PPM. Then add nutes on top of that, but don't exceed more than around 400PPM until the plants are well established and flowering. Just a normal diet down the middle while building mass. Then, when flowering you drop off Cal Mag and replace with the stinky shit like Sulphur to get the
terpenes happening.
Do you run CO2? What lights / size of grow? How often are you doing a water change? Are you using biologics or running a sterile res? What are the plants in, like CoCo or Hydroton or Rock Wool? RH and Temp control? If you want to post pics of your whole system, I'll make suggestions.
