From The Aquarium Wiki
Acriflavine is a topical antiseptic. It has the form of an orange or brown powder. It may be harmful in the eyes or if inhaled. It is a dye and it stains the skin and may irritate. Commercial preparations are often mixtures with proflavine. It is known under a variety of names (trypaflavine).
Acriflavine is a preventative and treatment for the control of Oodinium (Velvet) in freshwater and marine fishes. It is also used as treatment for external fungal infections of aquarium fish.
It has a long history of usefulness in the control of fish diseases. Acriflavine is useful for fish egg disinfection, treatment of open wounds, and external protozoan infections. The chemical said to be effective in the control of the bacterial infection columnaris (Flexibacter columnaris). But is not usually applied for other bacterial infections. Acriflavine may also be used as an alternative to Malachite Green when it is known that certain species of fish may be sensitive (small Characins).
Typical found in aquarium treatment bottles as acriflavine chloride in 0.3% solution.
- Rumoured to stop the spread of viral disease Lymphocystis.
Typical treatment bottles with this chemical in it are:
- Rabomed by Hobby dohse
- Acriflavine by Kordon
- WS3 by King British - (Sinclair Animal Care)
- Myxazin by Waterlife - broad spectrum bactericide (contains Formaldehyde 0.12%w/w, Malachite Green 0.085% w/w, Acriflavine Hydrochloride 0.055% w/w) 
- ↑ Chemical information on the product