I don't think there's a way around it if they're all sharing out of the same reservoir, even
without running the additives. Why not simply move to smaller reservoirs and break
I run a vertical version of diy aeroflo style in perpetual style and the only way I can do
this is with redundancy in having multiple smaller systems. I'm sure it could be pulled
off without but you're either going to burn, stress, or not give the plants what they all
want when they want it.
If you're running hammerhead you should look into running mother of all bloom in conjunction
with it. There's a lot of people that are a fan of this bud booster combo, and for good reason.