As HC is a very thick, viscous liqued, I suggest you do your diluations at the highest volumns possible, ie: rather than taking 33 ml to make up one litre of developer use, say, 100 ml to make up 3.2l(posted 8296 days ago)with such a high ratio (1:31) a slight mistake in measurement (especially if you don't dissolve all of the HC in your measuring device) it is easy to make a weak solution.