Matthew and I built the second tried system for the water filters. We also made a list for what we needed for the other bucket systems. I found out that it is really 3 in of red sand in the water filters. In the whey, we have 3 ½ in of black sand in one bucket and 7 in of wollastonite in the second whey bucket. The whey filters still must be completed as well as the third system for the water. We did good today!