sand/silt in pool

[uaguyua]

Hi I have a 2hp pump with an older 400lb sand filter (4.9sqft). I am seeing about a pint of sand appear in the pool per week and the filter seems to return a high fraction of silt/dead algea and even very small leaves back into the pool. I've taken the filter apart and replaced the sand and checked for broken laterals. My question: if I have a small crack which I missed last time I disassembled, could that explain both the sand and debris? Or would a small crack in a lateral/hub only explain the sand? I could understand how silt/dead algeae might back it back into the pool, but how could something as large as a small mesquite leaf make it back through the filter?

thanks so much,
dan