I tried filtering the Magnesol with a 5 micron filter but it clogged. Fabman suggested letting it settle for 12 hours and sucking the BD off the top which I did. I then filtered thrua 5 and 1 micron filter. At no time did I run it through a pump for fear of shearing the magnesol. I'm hoping I can gravity feed it through a 10 micron filter (without waiting 12 hours for sepapation) and then pumping through a 5/1 filter. I'm awaiting an answer to that one. Stay tuned. I used 4"x 8" sock filters in a PVC pipe. Saw the plans here. See if you can search for them. Tom