AntiparasiticOTC AvailableFish

Malachite Green + Formalin (Ich Treatment)

Malachite green oxalate + Formalin

Drug Class

Antiparasitic

Available Forms

Liquid (added to aquarium water)

Approved For

Fish

Dosage Guide

Follow product-specific instructions. Typically 1 drop per gallon daily with 25% water change before each dose. Treat for 10-14 days minimum. Remove activated carbon during treatment.

This is a general reference only. Always follow your veterinarian's prescribed dosage for your specific pet.

Side Effects

  • Toxic to fish at high doses
  • May reduce dissolved oxygen — increase aeration during treatment
  • Toxic to invertebrates (shrimp, snails)
  • Stains silicone and decorations

Important Warnings

  • !Scale-less fish (loaches, catfish, tetras) are sensitive — use half dose
  • !Remove activated carbon from filter before treatment
  • !Increase aeration during treatment
  • !Carcinogenic with prolonged human exposure — handle with gloves
  • !NOT for use in food fish
  • !Not all white spots are ich — confirm diagnosis before treating

Contraindications

Do not use this medication in the following situations:

  • Tanks containing invertebrates (shrimp, snails)
  • Certain sensitive species (check species compatibility)

Medical Disclaimer

This medication guide is for informational purposes only. Always consult a licensed veterinarian before administering any medication to your pet. Dosages vary based on weight, age, health status, and concurrent medications. Never give human medications to pets without veterinary approval — many common human drugs are toxic or fatal to animals.