<p>Yes, David. Household ammonia varies widely in the level of solution; they also are difficult to obtain without surfactants and olfactory additives; moreover, the bottles occasionally state the solution level, and we for our own efforts when mixing up R3 always found that the stated level was significantly off for the purpose of consistent performance across batches. So mixing at home -- which we encourage -- has the difficulty of having to manage a consistent ammonia solution. This can be overcome in a well-documented, mature process by managing ratios or managing the ammonia solution directly; however, it is not like making pancakes. </p>
