Be careful when handling/ using Malachite Green because it's carcinogenic (causes cancer).
Avoid coming in contact with it.
If you are using a powder form of Malachite Green, wear rubber gloves and a dust mask, and an apron (or wash clothes after handling it.
Wash hands with warm soapy water after handling medications or working in the aquarium.
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Are you sure the fish have white spot and not something else?
If you post pictures we can check them to confirm it is white spot.
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The medication can break down if kept in warm/ hot environments or if exposed to direct sunlight. Check the expiry date to make sure it hasn't gone off.
The water usually loses the colour after 24 hours or so, depending on dose rate used and on what else is in the medication.
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The following link has information about white spot and has various treatments you can try if the malachite green doesn't do the job.
This is a common question that is often asked, what is ich and how is it recognisable and what causes it? The real term is ICHTHYOPHTHIRIASIS. OR commonly known as white spot. It is an extremely comon parasite that affects aquarium fish. It is highly infectious and potentially lethal and...
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