Crystallizing of Chemicals

[thefizz]

I recently noticed my opened bottles of Ilford Wash Aid and Moersch MT3 Sepia toner have started to crystallize at the bottle. My darkroom is cold when not in use so is this the cause and is it anything to worry about? Will it dissolve if warmed up or should I just filter it out?

 

[Ian Grant]

It should dissolve when it warms up. You might want to filter the solutions when made up though.

Ian

 

[Gerald C Koch]

I recently noticed my opened bottles of Ilford Wash Aid and Moersch MT3 Sepia toner have started to crystallize at the bottle. My darkroom is cold when not in use so is this the cause and is it anything to worry about? Will it dissolve if warmed up or should I just filter it out?

It's best not to store chemicals in the darkroom. These spaces are usually poorly ventilated. The problem is that chemicals like sulfide toners can cause fogging of paper and film stored there. Sulfide toners emit hydrogen sulfide which is a gas and a powerful fogging agent. In addition certain chemicals once they come out of solution can be difficult to redissolve.