When designing your cooling system remember that the filters are going to add load to you pump and reduce the water flow so some additional sizing may be required to compensate. I would consider using a side stream filter system that are used with boiler systems. You can go from 20 down to 1 micron filters. There would also be no issues using additives like glycol, rust inhibitors, etc. as these are routinely used in heating loops. House filters may not be able to tolerate `mixed water` or coolants.