The 'minimal level' is unknowable without a way to measure. but if you have bacteria - your levels are constantly being absorbed / used. Basically, you want a specific amount of free chlorine in the system as a sterilizer. A part of science I never knew about and have not heard mentioned on the forums.
I bought some pool test-strips to measure total and free chlorine.
I've been trying to guesstimate the oxidizing level in the RES.
Glad I kept with it, this grow has been challenging, but I've learned a ton. new growth, plants are straightening out. new roots are popping out everywhere, plants appear to be back on the road to recovery. I took out each plant and removed any dead roots, cleaned up what was left, flushed minimal roots with some h2o2 water. Refilled with Clear Rez and ran the system. but the system is nearly surgical clean again. Found lots of SHIT (bacterial clumps of growth) coming out of my piping. Drained, flushed the buckets, flushed again, and again with a strong h2o2 solution running through the pipes! Then, wiped it all down with strong h2o2. I was losing the battle against the brown algae - it was time for some drastic measures.
What a difference a few days make! Beneficial microbes were not working. 1/5 - did a complete system clean, flushed res and refilled.
