Conversion Coatings: Phosphate vs. Zirconium | Products
01/02/2018#0183;#32;The typical zinc phosphate bath should last about one to three months, an iron phosphate bath three to six months, and a zirconium bath six to 12 months or longer. Placing small cartridge filters, typically of 20 to 30 microns in size, in these baths also can significantly extend bath life.