I'm assuming that the idea is to fill equal parts pool water and reagent in the supplied bottle. Measures out to 15 mil and 15 mil. Is it possible to reduce to half the doses to be cheap or is this the required amounts for the size test tube. The reason I'm asking is that it is difficult to measure the meniscus especially at the top of the bottle. When I measure out two equal portions the bottle fills to the bottom of the neck not the top of the label. Next test I will measure equal parts with a medication cup and then put in bottle.