I recommend the Fleck 40922 bottom screen. This is a high flow, fine screen heavy duty bottom screen. Use 1/10 of a cubic foot of a garnet underbedding (8x12 is common) Assuming it is going into the 2510, the Fleck and Clack valves all go level with the tank. http://www.pentairwatertreatment.com...tributors2.pdf Here is the link to the specs and info on this bottom screen. Do not use a cheap bottom screen. Use only the heavy Fleck or Heavy Clack versions.