When to use?
When fish show symptoms of a parasitic or fungal infection, including white spots along the fins and body, flicking and rubbing, gasping at the surface, an opaque film over the body or fluffy, white growths.
How to use?
Do not use with orfe, rudd, tench or sturgeon/sterlet.
Do not use if the water temperature is above 30°C.
Do not use in hot, humid, thundery conditions.
Do not mix medications.
Q: Can I use FMG in a mixed-species pond? A: No. As this product is in our Koi Care range, it should be used in koi-only ponds. If you have a variety of species in the pond, our Pond range product, Eradick - Anti-Parasite & Fungus, is a more appropriate option; take a look. However, avoid using either treatment in hot, humid or thundery weather.
Q: Can I use FMG with salt in the water? A: Yes, provided this is at a concentration of 0.3% (or 3g/L) or lower. To accurately measure the salt concentration of your pond, use a hydrometer or ask your local fish shop to test a sample for you.
Q: How often can I repeat the treatment? A: You should wait 7 days after adding the dose before re-treating or using a different medication. Ensure you perform a partial water change after the 7 days have elapsed, regardless of whether another round of treatment is required.
Q: Can I leave my UV on during treatment? A: No, you should turn off any UV filters for 7 days from when you add the dose.
Q: Will FMG affect my water quality test results? A: No, so long as the colour has faded from the water. This should happen within a few days of the product being added.
For common frequently asked questions, click here.
Active Ingredients: Malachite Green 500 mg/100 ml, Formaldehyde 15000 mg/100 ml
250ml, 500ml, 1 Litre & 2.5 Litre
Let us calculate your dosage for you!
To make the process of using our products even easier this handy dosage calculator tells you the amount you will need to put into your system. Please ensure you also read the instructions and warnings that are written on the bottle/pack label.
Note: This calculator does not take into account water displacement such as that caused by substrate, ornaments, water features and plants etc. Therefore, please adjust the calculated volume accordingly.
I know my system's measurements and want to:Calculate my volume
10 m per 80 gallons (364 litres). If necessary, perform a partial water change and repeat the treatment 7 days after the previous dosage. The treatment can be safely repeated up to 4 doses.
* Always follow the instructions on the label. This calculator is intended to be used only as a guide to how much product you need to buy to treat your system. It does not take account of displacement caused by gravel, rocks and ornaments etc and does not include the volume of any external filtration system. NT Laboratories Ltd. will not accept any responsibility for inaccuracies or misuse of this guide.
Keith Holmes - Koi Waterbarn from Knockholt, Sevenoaks
Koi Water Barn and NT Labs have a long history of working together, we feel that the products in the Koi Care range offer our customers a quality product at a realistic price. This is backed up by extensive research and development that is carried out at the NT Labs HQ located in Kent. They are not far away from our shop at Coolings (Knockholt, near Sevenoaks), this is an added bonus for our customers as they are buying from a local UK based company.