The potions which used to rinse photos : Whether you rinse photos or film ,there are :developer, stop and video solution ,fixing solution.
The developer:Its composition is
silver bromide, we see the black-and-white photos is actually a reduction from the silver particles
The stop and video solution:The film or photographic paper image before entering the buffer solution, its composition is
acetic acid, temporarily fixed image so that the image will not span.
The fixing solution:Solid image firmly in the paper or film, the composition of
sodium thiosulfate .