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How To

How to: Treat with Malachite and Formalin

Medicating a pond can sometimes be a little confusing. Many people have different views and opinions about which treatment works the best and how often to treat the fish – it can get unnecessarily complicated!

One treatment, probably the most popular, is called Malachite and Formalin. This treatment is commonly used throughout the world of fish keeping and is effective against many ailments.

Malachite Green has excellent anti-fungal properties. It can be used on it own but is better use with formalin.
Formalin is a disinfectant used to deal with many popular parasites, but again works better when used in conjunction with Malachite Green.

During the treatment process your water will be dyed blue, this only lasts a few days and will clear up.

The first step is to calculate the volume of your pond in gallons: average length in (ft) x average width in (ft) x average depth (ft) x 6.25

For a round pond: 3.142 x radius squared (ft) x depth (ft) x 6.25

This will give you answer in gallons. To calculate the quantity required of each solution, use the following method:

Malachite = Pond volume (gallons) x 17.6
Formalin = Pond volume (gallons) ÷ 220 x 15

This will give you an answer in ml. Add the required amounts to a CLEAN bucket or watering can and fill with pond water. Give the mixture a good stir and then spread evenly over the surface of the pond.

Some important steps should be followed to ensure the pond is treated safely:

  • Turn UVC off for 2 days but leave the pump running
  • Stop feeding for 2 days (including day of treatment.)
  • Ensure there is sufficient oxygen in your pond.
  • Keep biological filter running throughout the treatment period.
  • DO NOT use any other treatments for a minimum of 7 days before or after use of malachite and formalin.
  • Repeat the medication after 7 days

It is also a good idea to keep a close eye on the quality of your water by testing pH, ammonia and nitrite levels. If you use salt in your pond, ensure that the level is at a maximum of 1/4 oz per gallon (0.16%).

Knowledge: How are Koi Carp measured?

It is often taken for granted the huge process it takes to get our beloved Koi Carp all the way from the specialist fish farms in Israel; 2500 miles away!

This video clip shows how the Koi are sized before they are shipped across the globe. The Koi specialist manually sizes each Koi by hand to double check the fish is of the correct size before being placed into the shipment bag. This also gives the Koi specialist a chance to “health inspect” the Koi prior to packing.

How to: Introducing your new Koi to your pond

It is important to introduce your new Koi Carp to their new environment in the correct way to ensure their safety.

STEP 1: Remove the bag from the box and carefully place into the pond.

STEP 2: To allow the water temperature in the bag to gradually equalise to the temperature of your pond water, we recommend floating the bag for around 20 – 30 minutes. This is essential to ensure the temperature change doesn’t shock the fish.

STEP 3: After this time, open the bag and gradually fill it with pond water a little bit at a time. Repeat this step about 2 or 3 times in 5 minute intervals. This will allow the new Koi to adapt to the chemistry of the new pond water.

STEP 4: Finally, do not feed your new fish for a few hours. Give them time to adjust to their new surroundings and settle in.

STEP 5: Enjoy your new purchase!