Photofinish darkroom cleaner is a non-toxic, biodegradable, general purpose darkroom cleaner in paste form, which will not contaminate photo chemistry. It is particularly effective for removing chemical deposits and developer tars from tanks, trays, and roller transport equipment. It is also excellent for removing chemical smells from skin.
Photofinish can be safely used to clean almost all materials and is designed for use on both tabletop and stand-alone machines, as well as tanks, trays, reels, sinks, counter-tops, etc. It will not damage most plastics, metals, hard or soft rubbers, nor will it scratch the passivating layer on stainless steel.
However, because Photofinish does contain a very mild abrasive, excessive rubbing on some materials, such as plexiglass, could scratch the surface. Use of force is not recommended, nor is it necessary. Stubborn stains can be removed through repeated applications. Photofinish is specifically designed to clean processing machines of all types of B&W and color developer tars (including EP2 and RA4), bleach, fix and stabilizer residue. Stains from water deposits (mineralization), scum, algae, and most toners are also easily removed. Because it contains a mild abrasive, you should not use it on surfaces or plastics where the optical quality of the finish is important.