Gold To Blue Fish For You

The genus of fish that we all affectionately known as “Tuskfish” are famous for their dramatic changes in coloration as they transition from juvenile to adult. They all start out life as female, with generally gorgeous and intricate patterns, and then at some point, change into their adult outfit, which is also usually gorgeous (even if it is sometimes less intricate), and sometime after that, they will all turn male. Thus, the largest Tuskfish you encounter will always be male! In the case of Choerodon schoenleinii or the Golden Tuskfish, it gets this common name from its juvenile coloration, which is a gorgeous shade of yellow/gold with iridescent blue facial markings and a prominent black spot high on its back.

As the fish ages into adulthood, this black spot is one of the few features it will retain and is the genesis of another of this fish's common names, the Black Spot Tuskfish. Its color will become a deep blue/green with fins and a chin that can look almost purple. Some specimens will also develop a bright yellow belly and all these features play into even more of the common names we see: Yellow Belly Tuskfish, Blue Tuskfish, and Purple Groper (and Grouper, even though it is definitely not a grouper). Worldwide, Choerodon schoenleinii has dozens of common names, which is a testament to its popularity, not as an aquarium fish, but as food. It is allegedly very delicious and is harvested far more frequently for this purpose than it is collected for fish tanks.

In the wild, Golden Tuskfish are usually found in fairly shallow water. While widely reported to be seen and caught from depths as far down as 200 feet, they are generally encountered around tropical and subtropical reefs less than 65 feet deep. They can be found all throughout the Indian and western Pacific Oceans where they mostly eat crustaceans like shrimp, crabs and shelled bivalves. In fact, Choerodon schoenleinii has found itself the subject of several scientific papers because they have learned how to use rocks like an anvil. They will pickup hard-shelled invertebrates and smash them against the rocks to break them open, fitting the description of “tool use” as it is generally applied.

Knowing all this, it isn't hard to see how one needs to feed Golden Tuskfish. They need large, protein heavy meals that consist largely of invertebrate matter. Smaller individuals will do well on things like Gamma Mysis, Krill, and Bloodworm once or twice a day. As individuals age, they will need larger (but less frequent meals). Gamma's Cockle In shell is a nearly ideal food, as are whole, shell-on market shrimp and crabs. They will happily take live earthworms, as well as appropriately sized chunks of Silverside. We have had great success in getting smaller individuals to take Nutramar Marine Complete Sinking Pellets, which is a nearly perfect diet for them. This product is also available in a larger pellet at 12mm, which is a great choice for these fish into adulthood.

Adulthood is a topic we can't brush past as these beauties definitely qualify as monster fish. They can allegedly get to almost 40 inches long and 33 pounds, but we can't find a concrete example of a fish this large. The world record according to the International Game Fish Association doesn't have a listed length but did clock the scales at a whopping 20 pounds 15 ounces; this fish was caught in 1988 by Ms. Olga Mack in Australia. Golden Tusks will reach adulthood and be sexually mature (as females) at about ten inches long, and you're very unlikely to see a specimen larger than two feet long; still a daunting fish to house in the home aquarium. As a result, the absolute minimum tank (or saltwater pond) size we suggest for these fish is 300 gallons, and more would be needed for the largest specimens. This tank should be tightly covered, and should feature both very stable rockwork and open spaces for them to swim in. They will not require a substrate as they do not use it for sleep; if you choose to include sand, choose a larger grain size as Golden Tuskfish will blow sand around as they hunt through it for prey.

A fish this big, with this kind of appetite generates a lot of waste. As a result, the filtration for their display also needs to be quite robust. While they don't necessarily require a ton of current, they can handle it, and so we suggest using a filter system that will overturn the whole volume of the aquarium at least ten times an hour. Large and frequent water changes will also help maintain a nutrient level that is appropriate. While these fish are very hardy and not over sensitive to elevated nutrients, we still suggest keeping the nitrate level under 15ppm. Lower numbers will make it easier to maintain a healthy dissolved oxygen level and will also aid in inhibiting excessive algae growth. Salinity should be stable but could be anywhere from 1.020 to 1.025. The pH of the system should rest as stably as possible between 8.0 and 8.4. As referenced earlier, Choerodon schoenleinii can be found in both tropical and subtropical locations, and as such, has a wide range of temperatures it can be kept at; we suggest a display temp between 72 and 78 degrees Fahrenheit but if acclimated slowly, they could easily be kept in temperatures ranging down to the mid 60s.

Like most Tuskfish, Goldens are generally peaceful fish that will do well with most other fish. Initially they can be somewhat shy and might get bullied if you attempt to house them with established, aggressive fish. Once they get used to their environment, they will be very active. They are very low direct risk to your corals but aren't seen much in reef-type aquaria because of their large size, “bull in the China shop” activity, and the large amount of waste they can produce. They are a very real and direct risk to small inverts like crabs, sea urchins, shrimp and especially clams.

Very few of these incredible fish show up in the aquarium hobby, so it’s quite a treat to see them here at Quality Marine. Golden Tuskfish are amazingly beautiful and hardy fish that do well in a wide variety of aquarium types, as long as those aquariums are large enough. If you have just such a display and are looking for a Tuskfish that most people haven't seen, then maybe Choerodon schoenleinii should be on your list! Ask your Local Fish Store about getting you an example from Quality Marine today!