Gem Tang

Published July 30, 2019
Author: Mike - FishLore Admin
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The Gem Tang fish (Zebrasoma Gemmatum) is also known as the Spotted Tang. Is it called the Gem Tang due to it's enormous price tag?

The spotted tang is likely the more descriptive common name given their markings. They have numerous white spots on the head and body with the spots primarily being round on the fins and head but elongated elsewhere.

You are probably wondering why this fish is so expensive? The main reason is that it is rarely collected and hardly ever seen in the aquarium trade. If you do happen to see this tang on sale expect to pay around $3,000 for it! In the ocean they are found near reefs at depths of 30 to 200 feet in the Western Indian Ocean near South Africa, Mozambique and a few other locations.

Gem Tang

Gem Tangs are considered just as hardy as the other Zebrasoma tangs and adapts well to being in an aquarium. Give them a tank that is at least 120 gallons but preferably much larger since they like to swim. Try not to keep them with other tangs because they may fight. That warning is doubled if you plan on keeping them with other Zebrasoma species. Some hobbyists have been fortunate in keeping multiple tangs in the same tank. If you do plan on keeping multiples introduce them at the same time and be sure there are plenty of hiding places. If the fighting gets to be too much be prepared to separate them. Given the price tag of this fish, I don't really think keeping multiples will happen except in the larger tanks or public aquariums though.

This fish is an herbivore so they need to be given marine seaweed on a regular basis. I feed my tangs nori daily and mix in thawed finely chopped marine origin meaty foods (like Rod's foods or similar), along with a high quality pellet food like New Life Spectrum.

The hard part about keeping the Spotted Tang is actually finding one for sale in the first place and then having the available funds to buy one! They are considered rather easy to moderate to keep just like many of the other commonly available Zebrasoma tangs. Acclimate them to your tank (or even better, use a quarantine tank) over an period of an hour or two and keep a skunk cleaner shrimp or red fire shrimp with them to protect your investment.

Zebrasoma gemmatum

Gem Tang Care

Scientific Name : Zebrasoma Gemmatum

Common Names : Spotted Tang

Care Level : Moderate, needs an aquarium with lots of swimming space.

Size : 8.5 inches (up to 22 cm)

Life span : 7 to 10 years and possibly longer

Water Parameters : pH 8.1 - 8.4 | Temperature 74°F - 82°F (24°C - 28°C) | SG 1.021 - 1.025 | Carbonate Hardness (dKH) 8 - 12°

Origin / Habitat : Lives in coral and rocky reefs at depths of 30 to 200 feet (10 to 61 meters) and found in the Western Indian Ocean: Near Mozambique, South Africa, Madagascar, Reunion and Mauritius. They are usually found as lone specimens and are very territorial on the reef.

Temperament / Behavior : They will fight with other tangs especially other Zebrasoma tangs. They should leave other fish species alone and can usually handle themselves against other similarly sized fish.

Breeding : Has not been bred in the aquarium. They are open water egg scatterers.

Aquarium Size : 120 gallon (454 liters) minimum. Larger than 120 gallons is better to allow for adequate swimming room.

Reef Tank Safe? : Yes

Tank Mates : Keep with similar sized fish species, avoid keeping them with other tangs. Use caution if you do stock them with other tangs and introduce them at the same time.

Fish Disease : Saltwater Fish Disease - cryptocaryon (ich) is common.

Diet / Foods : They will pick at the live rock in the tank all day long and they need a steady diet of marine origin seaweed (nori). Seaweed selects from Ocean Nutrition (brown, purple, green marine algae) are very good. Mix in some meaty foods such as brine shrimp, mysis shrimp and other finely chopped pieces of meaty marine origin foods.

Tank Region : All over

Gender : Don't know of any external characteristics to determine males from females.

Forum : Tang Forum

Photo Credit : Photos copyright

Site References :

References :

"Zebrasoma Gemmatum". FishBase. Ed. Ranier Froese and Daniel Pauly. November 2005.
Randall, J.E. 2001 Surgeonfishes of Hawaii and the world. Mutual Publishing and Bishop Museum Press, Hawaii.

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