Methylene Blue
Methylene Blue
UPDATED: September 7, 2026
Information
This is a stock item that should be in every aquarist medicine cabinet. Also is the blue dye for tie-dye projects.
Composition
3,7-bis(dimethylamino)-phenazathionium chloride
Synonyms
Methylene blue-B; Methylthionine chloride; Urolene blue
Uses or Treatment for
Dye; antifungal agent on fish eggs; fungicide(Saprolegnia); external protozoacide [Ambiphyra(Scyphida), Chilodonella, Costia, Cryptocaryon irritans, Epistylis, Ichthyophthirius, Oodinium, Trichodina(Cyclochaeta), Trichophyra ]; Monogenetic trematodes(Cleidodiscus, Gyrodactylus).
Administration and Dosage
Preparation Methods
Observations, Notes, Remarks
When I make my stock solution, I add 7.5gm(1Tblsp) to 1 gallon of water