Symptoms:

• Darting around tank or rubbing against glass or ornaments. I mistook this for chasing a reflection.
• Clamped fins
• Lethargy
• Lack of appetite
• Labored breathing
• Color loss
• Gold, yellow, or rust colored dust on fish's body, fins or gills. Dust may be clumped into patches. To check for this, turn off aquarium lights and shine a flashlight on your fish.

Note: Your fish may only exhibit one or two of the symptoms, but the most important one is the visible dust on your fish. Clamped fins, lethargy, labored breathing and lack of appetite are signs of an advanced case. Many people mistake velvet for one of the white and fuzzy diseases and is often missed.

What is it?

Velvet is a parasitic form of algae. It is a dinoflagellate, like ick/ich, but it also contains chlorophyll like plants so it is an algae. Velvet is present in both fresh and saltwater aquariums. It attacks stressed fish by attaching themselves to the gills and sucking nutrients straight from the fish. The gills are attacked first, and then the rest of the body.

How did it get there?

Velvet attacks stressed fish. Any time there is a drastic temperature fluctuation, a change in tanks or poor water quality, your fish is at risk to acquire velvet. Any new fish should be quarantined for a few weeks before being added to a community tank. Since velvet is highly contagious, a community tank would suffer greatly from a stressed new arrival.

Treatment

Active ingredients to fight velvet are copper sulfate (CopperSafe, Velvet Guard) or malachite green (Maracide) Copper sulfate is commonly used to kill algae in ponds. Care must be taken while using medications containing malachite green as it will stain everything and is actually poisonous if ingested. These medications tend to be very stressful for your fish and will probably cause a difficulty in breathing since the oxygen in your water is being replaced by medication. Adding an air stone if you don't already have one would be beneficial. Lowering your water level so that your bettas have less distance to swim to reach the surface would also help them out. Methylene blue is a nifty little chemical that helps your fish breathe and would be beneficial to add along with the the velvet treatment to give your fish an easier time.

Note: Velvet has a stage where it detaches from the fish and multiplies before reattaching to either the same fish or a new one, so even if you can't see it anymore, follow all of the instructions on the medication you choose carefully.

Prevention

• Quarantine all new fish for several weeks before adding to a community tank
• Add a small dosage of CopperSafe to the water after doing large water changes.
• Use aquarium salt in your aquarium. Do not add every water change or you will over salt your fish! Add every 5th or 6th water change.
• Keep water clean. If you have a filter, perform a 20-30% water change every week, otherwise 70-80%. Be sure that your water is treated with water conditioner and is approximately the same temperature as the tank when adding.