Infusio

They can both use roughly the same amount of nutrients. EC 1.6 with a PK-Booster like PK 13/14 I would feed them both with the same nutrient solution till your more matured plant (she is looking gorgeous) reaching time to flush. Then I would disconnect that one from the automatic system and flush her manually.

If you feel they need different concentrations of nutrients you would need two different bottles and drip lines. They look like they are being fed by a gravity IV drip like setup, this is a fun idea! working in the medical field? I really like this idea I just don't know how practical it would be for myself. You would need to add the premixed feeding solution to the bottles and that's how you would do it. Or add a splitter into the drip line, but its never a true 50/50 split and one side would 100% get more then the other so the double bottle system I feel would be much more controlled and stable. I think this is the question you where asking, If not reach out and clarify. your DM or direct mailbox is the little green paper airplane icon at the bottom right hand corner of the web page. Best Of Luck!

Ok ... I guess I'm not understanding the question... I thought you wanted to give one plant a nutrient that you didn't want to give to the other??? ... you want to add some PK to the feed? Why wouldn't you just add it to your reservoir? Doesn't your reservoir feed/water all the plants? What am I missing?!

If you're watering from the same reservoir, you can't... but depending on the nutrient one needs and not the other (which you didn't specify), there might be something you could top dress that would take care of the problem. Good luck!