C
ct guy2
I'd like to clarify a little. The nutrient cycling which CT guy mentions does actually have an effect like a fertilizer. It takes place primarily in the function of flagellates or naked amoebae consuming bacteria/archaea and in turn releasing nutrients in a form which plant roots can uptake, thereby providing instant nutrient.
This is the main reason why I use ACT.
On the perpetual brewing, it is more likely to end up with a giant population of ciliates and very few bacteria/archaea. The only way to bring this around to a diverse ACT again is to add more food and wait for the cycle to come around again. It is much more practical to start a new batch.
I would say the cut off for a potentially healthy brew time could be as long as 48 hours, depending on variables.
I'll look into re-wording that again based on our conversations. I do agree with what you wrote. My attempt was to convey the mechanisms associated with ACT are very different than when applying seed meals or other organic fertilizers.