My own stopbath...hmm...a lot may use it, but I found out myself...

It's odourless...

To make 1 litre

* 5-10 grams of citric acid (powder)
* Water to make one litre

Use as it is.


Concentrate

* 100 grams of citric acid (powder)
* Water to make one litre

Dilute 1+19 for working solution.


I don't use any indicator as the stuff is so cheap I can use it as use-and throw-away. This is good for me as I don't have my own dark room and have to transport my chemicals to and from my home every time.