Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Yellow tangs

Yellow tang
Yellow tang


I've lost track of how many I've helped rehabilitate in the past three years and every time I had to bring them back it got harder and harder. I was amazed at how attached I became to these little fish and how each one was so different and unique from the previous ones. They each have their own antics and the last one I had decided to adopt my clownfish and wouldn't swim more then a few inches from the clowns. When I returned that particular Tang, the LFS didn't have any new ones in stock so I went home without a new one and noticed that my clownfish looked lost without their buddy. After that I decided that I didn't want to keep returning fish just as I was getting really attached to them and that I would wait until I had a tank that's more suitable for a full grown Tang before I get another one.


Yellow Tangs mostly found along the reefs and coral lagoons in the Pacific Ocean. They are found in depths from 2 to 45 meters. Most Yellow Tangs are imported from the Hawaiian Islands. In the wild they are commonly found singly or in small groups where food is more abundant.


In the wild the Yellow Tang can grow up to 8", in a tank 6" diameter should be expected. Young Yellow Tanks have a rounded body, as they mature they become boxier in appearance.

Social behaviour

When first introduced to a tank, they are generally fairly skittish and will hide a lot and may reject food for a couple days. Once they become more familiar with their surroundings they can become territorial and attempt to dominate the tank. They protect their sleeping area and grazing areas from other fish. They should not be kept in a tank with other Yellow Tangs once they start to mature or they tend to fight for dominance.

They are active swimmers and can dart from one end of the tank to the next in the blink of an eye. Ideally they should all be kept in tanks a minimum of 48" in length so they can have the required swimming room.

When stressed they become a pale milky whitish-yellow and are more apt to contract marine white-spot. When they sleep, they tend to hide and take on sleep mode colouration, brown patches on their sides that look like bruises with a horizontal white stripe through it.

Water Conditions
Specific Gravity - 1.022-1.025
Ammonia - 0pmm
Nitrite - 0ppm
Nitrate - 10ppm (max)
pH - 8.0-8.4
Calcium - 380ppm - 450pmm
Alk - 3-5meq/l or 8-14Kh
Phosphate - 0.02 mg/l (max)
Temperature - 26 - 28C (79F - 83F).

Feeding Habits

Yellow Tangs are herbivores that need a constant supply of food to graze on. They will eat most types of macro algae that grow in a tank including hair algae and all types of caulerpa. Their diet should also be supplemented with vitamin-fortified seaweed, blanched romaine lettuce or algae pellets, zucchini, or Spirulina. I have found they prefer re-hydrated green seaweed to the red or purple seaweed that's available. When using vegetables as a staple food they need to be blanched for about 5 to 10 seconds to break down the cellulose that Tangs aren't able to digest properly. , Avoid using iceberg lettuce, as it has little to no nutritional value. There are also frozen foods available for marine herbivores that most Tangs will accept as well such as the Emerald Entrée. They can also be trained to accept high quality flake foods as well, but I haven't had any luck with that endeavour.


In the wild they have been observed to both group spawn and pair-spawn. They haven't been spawned in captivity as of yet.


Over the years, I have cared for many of these wonderful brilliantly coloured Yellow Tangs for short periods of time to help them adjust to the captive environment.

 The LFS I normally went to constantly had many newly imported small tangs about 1 inch in diameter with shredded fins and their bellies were starting to collapse, most of which ended up dying in those tanks. I had wanted to keep a yellow tang for a long time, but I knew my tank, at 30" in length wouldn't be the ideal conditions for a yellow tang to reside in since they are normally very active swimmers and require a tank with a minimum of 48" length for swimming. However, after seeing the LFS fill a tiny 24" tank with 10 or so of these tiny 1" specimens

I figured that I would be able to help at least one of them stand a better chance in an lightly stocked, mature tank then they had in the tanks at the LFS. I made a deal with the LFS that I nurse one back to health and after a month or so, depending on how well the tang recovered, I would return it in exchange for another newly imported Tang. This worked out well for both the LFS, as they got health specimens back that they would be able to sell, and I got to keep a fish that I really liked.