Most saltwater fish hobbyists fear a marine velvet outbreak more than anything else. It’s one of the most lethal fish diseases and can quickly wipe out an entire tank. However, this condition doesn’t need to be the end of the world. Treatment may be possible while a fast-acting owner can mitigate the damage by quarantining affected fish. In this guide, we’ll look at everything you need to know about marine velvet and how to reduce its potential impact.
Marine Velvet Is a Serious Fish Disease
Marine velvet is one of the most devastating saltwater fish diseases. Amyloodinium ocellatum is responsible for this condition. In short, this is a type of parasitic plankton that can wreak havoc in aquariums. Marine velvet produces sugar-like grains that spread across the body of affected fish. The organism is very hardy and agile as it is a free swimmer. This makes it easy for it to quickly infect other fish. It can also survive dramatic temperature and pH ranges.
Stress Commonly Causes Marine Velvet
The main cause of marine velvet is introducing new fish into an aquarium. Experienced owners know that it’s essential to quarantine fish for up to a month before putting them in the main tank. This is the easiest way to drastically reduce the risk but it’s not foolproof. It’s also worth noting that marine velvet is more prevalent during summer months. Avoid buying new fish during this hot period because it increases the risk of bringing the disease into your saltwater aquarium.
Marine velvet is present in the wild, but it’s not as dangerous. Aquariums are contained environments where the disease can spread rapidly instead of dissipating. Stress is one of the main triggers of marine velvet. Transporting fish is a very stressful experience and can seriously impact their immune systems. This reduces their ability to fight marine velvet or other parasitic conditions.
Quarantining and feeding new fish properly are two ways to mitigate this. Healthy, non-stressed fish are less likely to cause an outbreak in their new home and spread marine velvet to the existing population.
Symptoms of Marine Velvet
The problem with marine velvet is that it’s often too late when it starts displaying symptoms. We’ve already mentioned the sugar-like grains that spread across the fish’s body. Other common symptoms include rapid breathing and discolored eyes and fins. Disorientation may occur, with the affected fish swimming into the side of the tank or its decorations. They may even scratch themselves furiously.
Options for Treating Marine Velvet
Treating marine velvet is tricky because there’s often not much we can do to save the fish. The most important first step is to immediately quarantine visibly affected fish to try and save the remaining tank population.
Ensure the aquarium water quality and tank parameters are balanced to help these fish fight off a potential infection. Ideally, you should remove the healthy fish from the main tank and place them in a sterilized environment for about a month, which may involve getting a third tank. This will allow the parasitic organism to run its life course without any host.
There are treatments for marine velvet including copper and chloroquine diphosphate. The former is toxic for invertebrates so don’t use it if there are any shellfish in your tank. Meanwhile, chloroquine diphosphate is very expensive but can be effective if you apply it quickly. Prevention is always better than trying to save sick fish. Remember, marine velvet can wipe out a saltwater tank in just hours. It can happen overnight and catch owners unaware.
Marine Velvet Can Affect All Fish Types
Marine velvet can affect almost every fish species. However, it appears that sharks and rays are two exceptions. Some fish are more susceptible than others. For example, bottom dwellers don’t experience it as often as top dwellers. This is because the parasite loves light. Blue tangs are notorious for contracting this condition, so be aware. Quarantine all new fish because this is the most effective way to reduce the risk it poses.
Marine Velvet vs. Saltwater Ich
Many new fish owners mistake marine velvet for the less serious saltwater ich. Both conditions produce similar symptoms by triggering white spots across the body. However, ich causes larger spots, and they aren’t as close together as marine velvet. This is another very common parasite that is also contagious. The good news is that it’s less rampant or devastating than marine velvet. It’s common for the spots to fall off the fish within 48 hours.
It’s possible to manage and treat saltwater ich much easier than marine velvet. However, saltwater ich has a longer life cycle than marine velvet. Treat it with copper. Usually, marine velvet doesn’t break out unless you introduce new fish to a saltwater aquarium. However, ich can occur at any time. Managing the water parameters is one of the best ways to block this nasty disease.
Does Marine Velvet Affect Invertebrates?
Invertebrates and corals won’t suffer any negative effects from a marine velvet breakout. However, it’s important to note that some treatments can seriously harm them. Copper is very toxic for inverts and coral. Don’t use copper if they’re in your aquarium. Instead, remove the fish from the tank and leave them in a backup until the marine velvet life course expires. Once the parasite has no host, it will die after about four weeks. It’s better to wait for two months just to be safe.
