i installed my coolant filter about 3 weeks ago i've done roughly 600 miles and changed it today i cut the filter open and there was nothing no sediment no particules i was actaully disappointed seems my coolant and engine are clean of casting sand and coolant debris

 

I don't think there is a lot of sand, just catches what comes off hopefully before it clogs egr and oil coolers!

 

You need to leave it on alot longer than 600mi. It is a "bypass" system which means the coolant isn't going through it all the time,only a small amount.