Yellow tang
Zebrasoma flavescens
Also known as: Lemon sailfin, Somber surgeonfish, Yellow sailfin tang
If you want a fish that actually puts in work, the Yellow tang is a nonstop algae grazer that cruises the rockwork all day. Its bright solid-yellow color is the whole reason people fall in love with it, but the real trick is keeping it well-fed on greens so it stays chunky and less cranky. Give it strong flow, high oxygen, and enough swimming length and it will act like the little yellow boss of the reef.
The Yellow tang features a vibrant yellow body, a laterally compressed shape, and a prominent spine on its tail.
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Quick Facts
Size
20 cm
Temperament
Semi-aggressive
Difficulty
Intermediate
Min Tank Size
125 gallons
Lifespan
10-20 years
Origin
Pacific Ocean (especially Hawaiian and other Pacific island chains)
Diet
Herbivore - nori/seaweed, spirulina and algae-based pellets/flakes, plus some frozen foods as variety
Care Notes
- Give a yellow tang real swimming room - I'd call 75g the bare minimum, and bigger is way easier on aggression. Lots of live rock for grazing plus a couple caves so it can wedge in at night.
- Keep salinity steady around 1.025-1.026 and temp about 76-79F; they get cranky fast when those swing. Nitrate in the single digits is fine, but if it's always high they seem to lose color and get more prone to ich.
- Feed algae first, not just meaty stuff - nori on a clip daily is the cheat code. Supplement with spirulina flakes/pellets and occasional mysis, but don't let it turn into a pure protein diet.
- They can be jerks to other tangs, especially other Zebrasoma (like purple tang) and new additions that look similar. If you want multiple tangs, add the yellow last and go bigger on the tank.
- Reef-safe with corals, but they'll mow down some nuisance algae and also pick at film all day. If they start sampling your LPS, it's usually because they're underfed on greens.
- Watch for marine ich and HLLE (head and lateral line erosion) - yellow tangs are basically magnets for both. Quarantine helps a ton, and HLLE often improves with more algae in the diet, vitamins, and running less dusty carbon.
- They like high flow and lots of oxygen; a strong return plus a powerhead keeps them active and breathing easy. If your tang is always hovering and gulping, check surface agitation and ammonia right away.
- Breeding in home tanks is basically not happening - they spawn in groups in the ocean and the larvae are a whole project. Don't buy a pair expecting babies; just enjoy the fish.
Compatibility
Good Tankmates
- Clownfish (Ocellaris or Percula) - they mostly mind their own business in the water column and the tang usually just cruises past them. Good everyday reef buddy.
- Fairy and flasher wrasses (Cirrhilabrus and Paracheilinus) - active but not pushy, and fast enough that a grumpy tang cannot really pin them down. Great for keeping the tank lively.
- Reef-safe gobies and blennies (watchman goby, tailspot blenny, lawnmower blenny) - bottom perchers that do their own thing. Just make sure everyone has a bolt-hole so the tang does not try to own the whole rock face.
- Cardinals (Banggai) or chromis - calm midwater fish that do not compete much for the same turf. Yellow tang usually ignores them once the pecking order settles.
- Dwarf angels with some attitude control (flame angel, coral beauty) - can work in bigger tanks with lots of rock breaks. Expect a little posturing at first, then they typically establish lanes and chill out.
- Bristletooth tangs (Kole or Tomini) - one of the better 'other tang' options since they look and graze differently. Add them carefully and give plenty of swimming room and algae stations.
Avoid
- Other Zebrasoma tangs (purple tang, scopas tang) - this is where the yellow tang turns into the bouncer. Same body shape means same rivalry, and it can be nonstop chasing in anything but a big tank.
- Another yellow tang - sometimes it works if they are introduced together as small juveniles, but most of the time one decides the other cannot live there. Not worth the stress in average home tanks.
- Fin-nippers and pushy semi-aggressive fish (some damsels, larger dottybacks) - they will poke the tang and the tang will escalate, and suddenly the whole tank is in a bad mood.
- Big bruisers that outcompete food and space (larger triggers, aggressive large wrasses, some puffers) - the tang gets bullied off the algae and starts pacing and picking fights back.
Where they come from
Yellow tangs (Zebrasoma flavescens) are classic Hawaiian reef fish. In the wild they spend their days cruising over rock and coral, picking at algae and hanging around reef slopes where theres constant water movement.
That lifestyle explains most of what they need in a tank: lots of rock to graze, clean oxygen-rich water, and room to do laps.
Setting up their tank
Give a yellow tang space first, then decorate. I like a longer tank over a tall one because theyre active swimmers and they use the whole length.
- Tank size: 75 gallons is a workable starting point for a single yellow tang, but 90-125 gives you a lot more breathing room
- Aquascape: lots of live rock with open swim lanes (think caves and arches, not a solid wall of rock)
- Flow: moderate to strong, with messy dead spots avoided
- Filtration: a real skimmer helps, and so does a refugium or other nutrient export if you feed heavy
- Stability: keep salinity and temperature steady (swings stress tangs fast)
If youre adding a yellow tang to an established tank, rearranging a few rocks right before introduction can cut down on territorial posturing. It breaks up the 'this is my rock' mentality.
Avoid putting a yellow tang in a brand new tank. They do way better once the tank has some age on it and you actually have algae films and micro-life on the rocks.
What to feed them
Theyre grazers. If you feed them like a once-a-day pellet fish, you will fight weight loss, crankiness, and disease. Think constant nibbling with a couple real meals.
- Nori/seaweed sheets on a clip (my staple - swap it out before it turns to mush)
- Quality herbivore pellets or flakes as a daily backup
- Frozen foods occasionally (mysis, brine, blends) for variety, but dont make it the main diet
- Spirulina-based foods and algae blends are usually a hit
Soak nori in a vitamin supplement now and then, especially if the fish is new or has been through shipping. It can make a noticeable difference in color and recovery.
Feed smaller amounts more often if you can. Even just adding a second nori session later in the day helps a lot, and it keeps them from deciding your coral gets sampled.
How they behave and who they get along with
Yellow tangs are usually peaceful, but theyre not pushovers. They can be surprisingly bossy about their favorite grazing spots, especially with other tangs or fish that look similar.
- Good tankmates: clownfish, gobies, blennies, wrasses, most reef-safe angels (with the usual individual exceptions), chromis, anthias
- Use caution: other Zebrasoma tangs (scopas, sailfin), other yellow-ish tangs, rabbitfish if the tank is tight
- Usually fine with corals: yes, but hungry tangs sometimes pick at fleshy LPS or zoas out of boredom
Mixing tangs is where people get burned. If you want more than one tang, plan the order, the tank size, and have a backup plan. A mirror trick or an acclimation box can save you a lot of drama.
One thing I like about them: theyre bold once settled. Theyre out in the open, doing their patrol, and theyre great at keeping certain nuisance algae in check (not a miracle worker, but definitely helpful).
Breeding tips
Breeding yellow tangs at home is not really a casual-hobbyist project. Theyre open-water spawners with a larval stage that needs specialized rearing. Its been done in professional setups, but its not like pairing clownfish in a 20 long.
If you keep a group in a very large tank, you might see dusk spawning behavior (rising in the water column). Its cool to witness, but raising the larvae is the hard part.
Common problems to watch for
Yellow tangs are hardy once settled, but they have a few repeat issues that show up again and again. Most of it comes down to stress, diet, and parasites.
- Marine ich (Cryptocaryon): very common on tangs, especially new arrivals
- Velvet (Amyloodinium): faster and scarier than ich - fish can crash quickly
- HLLE/head and lateral line erosion: often tied to nutrition, stray voltage, and long-term water quality issues
- Bacterial infections after a scrape or fight: watch for frayed fins or red sores
- Aggression stress: pacing, hiding, not eating, or constant chasing from tankmates
If a yellow tang stops eating and starts breathing fast, dont wait it out. Thats often the point where velvet or a bad ich outbreak is taking over. Have a plan for quarantine and treatment before you buy the fish.
The best 'treatment' Ive seen for long-term yellow tang health is boring stuff done consistently: stable salinity, lots of algae-based food, and low stress from bullying. Get those right and theyre usually rock solid.
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