Water 500 ml
Acetic Acid (80%) 11 ml
- OR - (glacial) 9 ml
Sodium Sulphite anhydrous 45 g
Water to 1 litre

Treat for 30 seconds.

SB-1a for lith

Water 500 ml
Acetic Acid (80%) 44 ml
- OR - (glacial) 35 ml
Water to 1 litre

Treat for 10 seconds.


SB-1 for paper

Water 750 ml

Acetic Acid (80%) 17 ml
- OR - (glacial) 13.5 ml
Water to 1 litre

Note: Always add the acid to the water slowly whilst stirring. It is hazardous to add the water to the acid.

Treat for 5-10 seconds.


Some bromocresol purple can be added to SB-1 to form an indicator stop bath. The solution then appears yellow when fresh, turning orange in use and purple when exhasted.