I have an older sand filter (15 years?) where the manufacturers label came off so I can't find the model number. I think it was manufactured by Sparco based on the the small bit of label that was left. The filter is 24" high 19" in diameter. I have a 12,700 gallon AGP with a 1.5hp Pentair Dynamo pump.
The filter seems to be working fine but when I removed the multiport valve it looks like the filter is only about 1/2 full of sand. How much sand should be in the filter?