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Malachite Green


Malachite green and formalin have been used as a multi-cure for fish diseases

It is particularly effective against ich, velvet disease, skin and gill fluke and

bacterial diseases like fin and tail rot.

It can be used for poor water quality, traumatic injuries and overcrowding problems as well as nutritional deficiencies.

It also has anti fungal properties which means it can be used to protect fish eggs

from getting fungus.

Formalin is a disinfectant which is used to kill off microorganisms. When it is used

together with malachite green it has a far greater effect ( most medication sold

has both MG and Formalin).

How to use:

5ml per 20 liter was recommended

repeat after 3 days if necessary

a water change is before commencing is a must

If using against ich, you must leave the filtration in order to destroy the parasite's

life cycle.

Also you should test for ammonia and nitrates just in case there is a spike.

Important Note:

*it is important to wear protective gloves and not inhale the fumes of formalin

*both these products are poisons and may even be carcinogenic.

*malachite green is reactive with light so UV lights should be turned off for

treatment. it is also reactive to activated carbon

*formalin is reportedly toxic to tetras, catfish and loaches


*finally don't use this product for fish that's going to be consumed( it is a poison)

from my experience

this product sold as multi-cure has proved to be literally a life saver

my fish was very sick from spawning activity but was

luckily saved and doing well the day after i used the product

it was also useful against fin rot

so i would recommend it to anyone!

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