Developer Shelf Life

As someone who works full time I am not able to dedicate as much time to film photography as I would like. I also like to experiment with different developers and processes. This means that I don't use up colour or black and white developers very quickly. This is one of the reasons why I use Rodinal quite a lot as it has a very long shelf life. Even half open bottles of Rodinal are said to last at least 40 years! Although the developer goes a dark brown colour, its still works fine.

The dark brown colour of myyear old half full bottle of Rodinal is nothing to worry about

Most other developers are not so flexible. I use Ilford Delta 3200 high speed film quite a lot and the best results are achieved by developing it in Ilford DD-X. DD-X comes in big 1 litre plastic bottles which is quite a lot a developer for me to use up even at 1+4 dilution. DD-X will last for up to 2 years in full bottles, but only 4 months in half full bottles. I therefore always decant it into small bottles to get the maximum shelf life. I have used DD-X that is up to 14 months old (but stored in small, full bottles) with no problems.

I decant DD-X into different size bottles to maximise shelf life

I got the little bottle in Boots (Chemist) the big one is a Tropicana Orange Juice Bottle, from McDonalds. 

Of course you never know how long the developer has been on the shelf of the store you buy it from, but I think Ilford's own shelf life figures are conservative anyway.

I do some C41 Colour home developing using the Tetenal kit (not as much as I used to as I'm in a black and white phase at the moment). Unlike the black and white developers, which I use 'one shot' (pour away after one use) the Tetenal chemicals must be reused. The quoted shelf life of the made up Tetenal chemicals is 6 weeks. The last batch I used seemed to be fine even after 12 months! I keep the chemicals in tightly sealed plastic bottles in a cool dark place.