Learn about how aquarium fish medications work and what diseases they may be used for.
The key to keeping your aquarium fish happy and healthy is to offer them a high-quality diet and to keep your tank water clean. Even if you keep up with all of your routine maintenance tasks, however, there may still come a day when one or more of your fish get sick.
For many aquarium hobbyists, a sick fish warrants a trip to the pet store for medication. What many aquarium hobbyists do not realize, however, is that sometimes aquarium medications can do more harm than good. So how do you know when to use medication and when to try something else? In this article you will learn the basics about using aquarium medications.
What Diseases Respond to Medication?
If you pay a visit to your local pet store and walk down the aquarium aisle you will find a number of medications for all kinds of different diseases. Unfortunately, many of the medications on the shelf are unlikely to actually have any effect on your fish. Certain diseases simply do not respond to medication which means that you’ll have to try something else. There are, however, two diseases which consistently respond to medication – fungus and ich.
Aquarium fish are prone to developing a number of different fungal infections and anti-fungal medications are generally effective in treating them. The four most common types of fungal infections seen in aquarium fish are cotton wool disease, gill rot, fin/tail rot, egg fungus, and systemic fungal infections. You will find an overview of each of these diseases below:
Cotton Wool Disease – The name cotton wool disease is applied to fungal infections that affect the skin, mouth, or fins of your fish, causing fluffy white growths to form. These growths often appear in areas that have previously been affected by fungus, parasites, or trauma. There are several different types of fungus which can cause this type of growth but the most common are Achyla and Saprolegnia. Cotton wool disease typically responds to treatment with aquarium salt or antifungal agents like phenoxyethanol.
Gill Rot – This fungal infection is fairly uncommon in aquarium fish, but it does occur and it can be deadly if not properly treated. When a fish is affected by gill rot it typically exhibits gills covered in mucus and it may be gasping at the surface for air. This type of infection is usually caused by the fungus Branchiomyces and it is most commonly seen in fish that are stressed by high ammonia or nitrate levels. Long-term therapy with increased oxygen levels and phenoxyethanol may be effective, though it is more common for treatment to be completely ineffective.
Egg Fungus – This type of fungus is very common, especially if the eggs are damaged or the water quality in the breeding tank is low. The fungus responsible for this are usually Achyla or Saprolegnia and they are present in most aquariums but generally do not manifest as infections unless the water quality declines. Unfortunately, once an egg develops fungus it cannot be treated but treating the tank with Methylene Blue may help to prevent infection.
Systemic Fungal Infections – Systemic fungal infections are fairly rare in fish and they are notoriously difficult to treat. The main type of fungus known for causing systemic infections is Icthyoponus and it can really only be diagnosed with certainty through a post-mortem examination. Fish with systemic fungal infections generally show signs of poor health and they will continue to decline until they die. In some cases, treatment with Malachite Green has been effective.
The only other disease that frequently responds to medication is Ich – this is the nickname for a protozoan infection known as Ichthyophthiriasis which is caused by the protozoan parasite Ichthyopthirius multifiliis. This disease is highly contagious and it is most commonly seen in fish that are already stressed, particularly in cases of poor water quality. This disease manifests in the form of tiny white spots on the fins, gills, and bodies of infected fish and it can spread rapidly. Treatment of this disease involves increasing tank temperatures to speed up the life cycle of the parasite in addition to treatment with Formalin or Malachite Green.
If you take a closer look at the medications available at the pet store, you will likely see things like antibiotics and medicated food. The problem with antibiotics is that they will not work unless you are able to identify the exact type of bacteria causing the disease and then match the antibiotic accordingly. Even if the medication does work to kill the bad bacteria, it will also kill off the beneficial bacteria in your tank which will cause a bigger problem. If you kill the beneficial bacteria in your tank it will cause the tank to re-cycle and that could result in toxic levels of ammonia and/or nitrate.
Does Aquarium Salt Work?
As an alternative to medications, many aquarium hobbyists use aquarium salt to treat common diseases. In fact, some aquarium hobbyists use low levels of aquarium salt regularly in their tanks as a preventive measure. In order to prevent aquarium fish disease, you could dose your tank with a maximum of ½ teaspoon per gallon. Just keep in mind that aquarium salt will not evaporate, so do not add extra salt when you are topping off the tank. If you perform a water change, however, you can dose the new tank water with aquarium salt at the same concentration.
The second option is to only use aquarium salt to treat infections – the most effective way to do so is to give your fish a salt bath. To prepare a salt bath for your fish, fill a bucket with aquarium water and make sure it matches the temperature and water chemistry of your existing tank water. Next, add about four teaspoons of aquarium salt per gallon of water and stir until it is completely dissolved. Next, catch your fish with a mesh net and place it gently in the salt bath. Allow the fish to soak for up to 30 minutes as long as it doesn’t show any signs of adverse effects. After the salt bath, place the fish in a quarantine tank and monitor for improvements.
As is true for any treatment method, salt baths do have their disadvantages. For one thing, it can be difficult to determine the right dosage for the problem at hand. Second, salt baths can be stressful for your fish – that is why you should limit the exposure and keep a close eye on your fish during and after the salt bath. It is also important to note that certain types of fish do not respond well to salt baths. This includes catfish (because they do not have scales to protect them) as well as certain species of tetra and barb. For these fish you may want to use a weaker concentration and limit the exposure.
Tips for Using Medications Properly
When one of your aquarium fish falls ill, your first move should be to quarantine it in order to prevent the spread of disease. If you suspect that your fish is sick with Ich, however, you should treat the entire tank for the infection. Make sure to follow dosage instructions closely and err on the side of under-dosing rather than over-dosing your tank. Monitor your fish closely after administering medication to make sure they aren’t having an adverse reaction and test your tank water frequently to make sure the medication doesn’t have a negative effect on your water chemistry. You should also read the instructions to see whether you need to remove the activated carbon from your aquarium filter.
Dealing with aquarium fish diseases can be difficult because there are so many different ways that aquarium fish disease can manifest. Not only can it be tricky to identify the disease, but treatment is tough as well. Do yourself a favor and take the time to make a proper diagnosis then select the best treatment option for your fish.
A recent paper published by the Conservation Research Group and the IUCN shows that more than 30 threatened species endemic to India are still being regularly exported, despite their conservation status.