Non-hardening Fixer Reduces Curl on both Film & Paper. Hypam Fixer can be Mixed with Hypam Hardener to become a Hardening Fix. Used 1 Part Hardener to 40 Parts Working Strength HYPAM Fixer, a 1 Litre Bottle of HYPAM HARDENER will Harden 902 Rolls of 35mm, 36 Exposure Films.