All the medicines mentioned in this article can be obtained in large quantities for reasonable prices. Yet none of them are used in commercial aquaculture of fish to treat any diseases (formalin is a notable exception). That is because they are either dangerous or they don’t work. The profit motive will always tell you a great deal about any subject. The aquaculture farmers operate on a thin margin and they don’t spend money on ineffective medications.
The profit motive also is the reason there are many false claims by medicine manufacturers that a product works. It is not illegal to falsely claim completely ineffective products cure a fish disease. False advertising is a way of life for many aquarium product manufacturers. It makes a lot of money for them. Aquarium supplies is a multi-billion-dollar business which is completely unregulated.
Some internet suppliers of aquarium medications compile all the hype that the manufacturers put out and publish it as “science”. New and even experienced hobbyists read these “papers” and “articles” and take them as factual. They are not factual! They simply parrot the claims of profit minded manufacturers.
A great deal of the positive feedback on some medications is from something called “anecdotal evidence”. One or a few people tried these medications and their problem went away. The problem with this type of evidence is that fish have immune systems, they can and often do fight off diseases on their own. So ANY medication will work a good percentage of the time.
If a human has pneumonia, they can often recover without the use of antibiotics. If a person recovers from pneumonia when they’ve only used herbs and publishes his experience on Facebook, do we then tell a relative with pneumonia not to take antibiotics but to take herbs?
Note that the big box fish stores and most local fish stores have stopped stocking any effective aquarium medications. The switch to “natural” medications has become the “in” thing and it is reflected in the stocking of fish stores.
Note also that the profit motive on “natural remedies” is huge. One can buy a 55-gallon drum of “Tea-Tree Oil” for peanuts and produce literally millions of small jars of tiny amounts of oil in water. All one needs in the water is enough oil to give the liquid a little smell.
While some of the medications listed below have some very limited uses, these “medications” are nowhere near as effective for everything claimed for them by zealous “believers” or profit minded suppliers:
Aquarium Science Website
The chapters shown below or on the right side in maroon lead to close to 400 articles on all aspects of keeping a freshwater aquarium. These articles have NO links to profit making sites and are thus unbiased in their recommendations, unlike all the for-profit sites you will find with Google. Bookmark and browse!