Many of you know that I have been working with water reuse systems for some four decades now. One of the first projects was the development (and sale) of a home wastewater recycling system. During it’s development, we found that certain high use conditions led to a buildup of ammonia in the returning (clean) wastewater to the toilet. Trust me, there are only so many times you can tell the homeowner that the ammonia smell means their toilet bowl is clean. (If you must know, once was about the limit!)