Yes, I'm reading from the beginning, although there seems to be some missing spots. Thanks for the quick heads up.
I do a similar airless RDWC, I just let a 1/2" line waterfall into each site, churning the water's surface. Would it be better if I were to run it through the hydroton instead?
Waterfall works, and feeding in through the hydroton works too. I cannot say which is better, but I'd imagine the more the water gets disturbed as it recirculates, the better. Both seem sufficient...
... on rollitup I think someone had actually purchased a dissolved oxygen meter and done some testing if I recall correctly...