From The Aquarium Wiki
Jump to: navigation, search

About Melafix[edit]


Melafix is a commercial antibacterial product made by Aquarium Pharmaceuticals, Inc.

The company claims "Heals open wounds & abrasions, treats fin and tail rot, eye cloud, mouth fungus and promotes regrowth of damaged fin rays & tissue. Will not adversely affect the biological filter, alter the pH, or discolour water. Safe for reef aquariums and live plants. For use in fresh or salt water."

Melafix contains active ingredient 1.0% Melaleuca (Cajeput or 'Tea Tree' Oil), water and an emulsifier to blend the oil into the water.[1] According to the USDA cajeput is the common name for both Melaleuca cajuputi[2] and M. linariifolia[3]. M. alternifolia is what is used to make tea tree oil[4].


Use 5ml for every 40 Litres (10.6US G.) of aquarium water. Repeat dose daily for 7 days followed by a 25% water change or until problem has gone.

What problems might it fix?[edit]

Mild cases of external bacterial infections (ulcers, fin tail rot).

It only works against low levels of certain types of bacteria and fungi (not necessarily all gram negative or all gram positive, but a combination of the some of each) on the skin of fish. Unfortunately, not enough studies have been done as to which types of fish pathogens they work best on. So it is currently up to trial and error of the individual aquarist.

  • It will not kill internal systemic bacterial infections.

We know in humans Tea Tree oil works against trichomoniasis (a one-cell parasite), as well as Tinea pedis (athletes foot), onychomycosis (a fungal nail infection) and Propionibacterium acnes (acne bacteria)[5]. M. leucadendra (sometimes confused with M. linariifolia) is “a stimulant, antispasmodic and diaphoretic, highly esteemed for internal and external pain, as a lotion for rheumatism, neuralgia, sprains, bruises, and toothache.”[6].

What problems might it cause?[edit]

Rarely some bacteria that are not affected by the oil may instead see the oil as food. This could cause a bacterial bloom making your water cloudy and/or removing oxygen from the water.

To prevent low oxygen increase aeration during use. If you notice your fish gasping at the surface do a large water change and discontinue use.

  • Do not overdose!

Read article 'Melafix and Pimafix - How They Work and Don't Work' below for more detail.


  • The patent is for the emulsifier, not for any medical effects.[7]
  • It may not cure fish related fungus, (mouth fungus is a bacterial infection not a fungus)


  1. 1 Product MSDS - English API 16 Nov 2005
  2. 2 PLANTS Profile for Melaleuca cajuputi Powell cajeput USDA
  3. PLANTS Profile for Melaleuca linariifolia Sm. cajeput tree USDA
  4. Tea tree oil (Melaleuca alternifolia [Maiden & Betche Cheel) 1 Feb 2008 Mayo Clinic]
  5. [Buck DS, et al. (1994). Comparison of two topical preparations for the treatment of onychomycosis: Melaleuca alternifolia (tea tree) oil and clotrimazole. Journal of Family Practice, 38(6): 601–605]
  6. [Hylton WH, et al The Rodale Herb Book Pennsylvania: Rodale Press (1974) pg380]
  7. United States Patent no 5,882,647 March 16, 1999