To mix as a film fixer, dilute 1:3 - 1:4. If hardener is necessary, use Fixer Hardener at 1 to 3 oz. per working gallon. To mix as a paper fixer, dilute 1 part fixer concentrate with 7 parts of water. Fix for 3-6minutes at 68ºF. Avoid overfixing. Temperature range: 68º - 95ºF.