d031b852_ध_रस_यन___क__स_च____व_क_प_ड_य___Source_and_description
[Chemical name] methylene blue [Chemical formula] C16H18ClN3S [Common or alternative name] Methidote [Source and description] 
Methylene blue (Methidote antiseptic) is used to treat small injured fish and is available at pet stores.
सरलता से उपलब्ध रसायनों की सूची - विकिपीडिया