Reply ===================== In this area we use submerged wells 1/2 - 1 HP . My HVAC installers used a 5 gallon bucket to test water flow before we started. The 1/2 HP or 3/4 HP can meet flows for two ton capacity though I went with a 1 HP replacement when my 3/4 HP failed in Jan 2011. Bear in mind that the small amount sand you are referring to represents A LOT of water that has flowed through the system during 5 or 6 months. There is no such thing as a well that pumps 100% pure water, unless you have an aquafer hundreds of feet deep. This is the water available to us, and it is pretty pure. I have shut off valves on either side of that housing, which minimizes possible "stir up" at the source end. I am also having fewing problems with the remaining TACO factory valve. Before putting that bowl in the TACOs were giving problems in 13 or 14 months. We are using a simple Franklin Electric submerged well motor which as I understand the design, passes or slings initial sand out before it gets to internal pump lobes or rotors. My well guy actually increased my warranty from one to two years and claims that standard single speed Franklin well motors in this class give him no problem whatsoever in this area as to longevity. He replaced the previous one when it freak failed at the 7 month mark. And THAT ONE went 11 years. I do not understand what you mean by "holding tank". Are you referring to an air bladder tank? In my situation, for some reason I already had two medium sized air bladder tanks probably purchased from lowes both piped into the system when the house was purchased. My well guy Raymond Golston does not think there are any problems with them, though I think he said it is possible to upgrade them and mentioned that as an option. I remember once when I replaced the Square D pressure control, opting for the lower pressure model because I felt the well motor would last longer.