TIL my water table has caught around 40 pounds of junk in 8 months

I was draining my water table last Saturday to clean out the sludge and figured I would weigh the bucket before dumping it, mostly as a joke. Scale said 41 pounds of dried slag and fine dust that never made it into the air. That number hit me hard. My shop is a one car garage in Reno with a roll up door I leave cracked, and I always figured the water did its job and that was that. But 41 pounds is like 5 pounds a month of stuff that would have been floating around where I eat lunch. Since then I added a second tray under the grate and started skimming the surface after long cuts instead of just topping it off. Curious if anyone here actually tracks how often they swap or filter their water, or do you just run it till it looks bad?