Eco Pro Clearfix Neutral Rapid Fixer (5 Gallons)

Ambient conditions will play a big roll in this. In extremely hot conditions, where oxidation is fast, you might be looking at 6 months. That being said, one should typically get about two years.

The Eco Pro Clearfix Neutral Rapid Fixer (5 Gallons) can make between 25 and 40 gallons of working solution depending on your dilution.

If you did not open the container the expiration date should not impact the fixer

Unopened Eco Pro Clearfix Neutral Rapid Fixer should be kept in cool, dark conditions. The products have a virtually indefinite shelf life. Once opened, the concentrate should be kept in tightly closed glass, PET(PETE) or HDPE containers, and used within twelve months. For best results in small scale darkrooms, a large opened bottle should be divided into several small glass or polyethylene bottles filled to the top to minimize exposure to air.

Not really suggest but you can extend the life of fixer for a year or longer after opening the bottle, pour the solution into smaller sealed bottles and just use test strips to check on chemistry.

Preferred options for disposal are to send to licensed reclaimers, or to permitted incinerators. Any disposal practice must be in compliance with federal, state, and local regulations. Do not dump into sewers, ground, or any body of water.

Collapsible containers are made of permeable materials that let oxygen in. I wouldn't recommend them for darkroom environments.

Clearfix Neutral Fixer from Ecopro (formerly Silvergrain) may be mixed at 1 + 4 dilution for film, RC paper or FB paper, or mixed at 1 + 7 for use with RC paper only.