from the blog

The Figure 8 Puffer: A Brackish Aquarium Fish

Caring for fish

September 30, 2020

When it comes to home aquariums, tanks are divided into two main categories: freshwater and saltwater. But what about the tanks that fall in between these two categories? Brackish aquariums are a mix of freshwater and saltwater and they are a unique challenge for the experienced aquarium hobbyist. Not only does the brackish aquarium offer interesting opportunities in terms of the tank itself, but you also have an entirely new category of fish to choose from. One of the most interesting fish for the brackish tank is the Figure 8 Puffer.

The Figure 8 Puffer By Till Kresslein (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia CommonsAbout the Figure 8 Puffer

The Figure 8 Puffer is a fairly small species, growing only as large as 3 inches at maturity. This fish is classified as aggressive, though primarily to members of its own or similar species. When housed with other fish, this species does fairly well. The Figure 8 Puffer is named for the unique patterning on its body. These fish have a white belly and a dark brown or green back with bright yellow lines and spots that form figure 8-like shapes. These fish are carnivorous and require a diet of brine shrimp, earthworms, krill, and crustaceans. To ensure that your Figure 8 Puffer lives a long, healthy life it is recommended that you purchase the fish as a juvenile and raise it with meaty, vitamin-rich foods.

Tank Set-up and Requirements

The main requirement for a Figure 8 Puffer tank is, of course, that it be brackish water. Aside from that, keep in mind that this species if a warm-water tropical fish so you should plan to maintain a tank temperature around 78°F. These fish also require a fairly high pH, around 8.0, so it is recommended that you use aragonite sand or crushed coral as a substrate in your tank to help keep the pH level high. Though the Figure 8 Puffer can live in freshwater, its immune system will be compromised and it will be more likely to fall ill. When kept in the proper conditions, these fish have been known to live well over 10 years in captivity. Plan to keep the specific gravity in your brackish tank around 1.005 to 1.008.

In addition to providing your Figure 8 Puffer with the right water parameters, you also need to pay attention to its preference for tank decorations. These fish are very intelligent and they become bored easily so you will need to provide plenty of interesting decorations for your fish to explore. Decorate your tank with a variety of rocks, plants, caves, and even plastic tubes to give your puffer plenty to keep him occupied. Though it is not recommended that you keep more than one Figure 8 Puffer in a tank, if you choose to do so anyway, having a large number of decorations in the tank to break up sightlines will be very important. If you do keep more than one Figure 8 Puffer in a tank it is best to buy them both as juveniles and raise them together.

Tips for Maintaining the Tank

Maintenance tasks for a brackish tank are no different than those for a traditional freshwater or saltwater tank. You still need to perform weekly water changes and replace your filter media on a monthly basis. In addition to performing weekly water changes, consider installing an EcoBio-Stone in your brackish tank to keep the water clean. EcoBio-Stones are made from natural volcanic rock, infused with live beneficial bacteria and the nutrients they need to thrive. Once you install the stone in your tank the bacteria will get to work, multiplying to establish and maintain the nitrogen cycle in your tank. Before you know it, your tank water will be clean and clear and your fish will be much happier for it.