Cichlid Fish Forum banner
1 - 1 of 1 Posts

1,365 Posts
There is no such thing as a hard date on any expiration date for a food or chemical. There simply isn't a way to tell what storage conditions the product is in so it's the manufacturer's best guess. And sometimes it's just arbitrary to determine when the product was made or to suit a retailer's needs.

Some chemicals, like inorganic salts, will never go bad. They don't decompose or go bad. Dry salts may absorb humidity and brick up. And solutions may lose water and become more concentrated but they don't change their chemical formula.

Others, like organic compounds will decompose into simpler molecules over time. Things like vitamins and amino acids will have a shelf life where past that they are likely to be ineffective. Dechlorinators will decompose into sulfur dioxide over time (that nice rotten egg smell).

The best way to tell if your test kit is still good is to test it against a calibration standard. You can buy premixed standards online for just about anything or you can mix it yourself if you have the proper components (and an analytical balance to weigh them out).

1 - 1 of 1 Posts