Rock Beauty Angelfish: a Finicky Feeder Best Left in the Sea

Rock Beauty Angelfish (Holacanthus tricolor)

Rock Beauty Angelfish (Holacanthus tricolor)

On one of my earliest dives down in the Florida Keys back in the 1990s, a gorgeous yellow and black angelfish caught my attention as I drifted over a section of reef. In my mind’s eye, I envision the angel hovering boldly above a large barrel sponge, but I can’t be sure whether that’s actually how it happened or just an idyllic memory. In any case, I was taken with its distinctive appearance and wondered whether it might make a good aquarium candidate.

As anyone familiar with the fauna of the tropical western Atlantic has already guessed, the angel I saw back then was a rock beauty (Holacanthus tricolor)—a species that, unfortunately, tends to fare poorly in marine aquaria and is generally best left to advanced fishkeepers or, better yet, in the ocean where it can beguile other divers. I’ll get into why in just a moment.

Physical traits

H. tricolor is laterally compressed (flattened from side to side) and, in typical angel fashion, sports a sharp, backward curving spine on the gill cover (operculum). As alluded above, this species is yellow on the anterior portion of the body and on the caudal fin and black from behind the gills to the caudal peduncle (base of the tail). The margin of the anal fin, the edge of the operculum, and the opercular spine are orange. The eyes are blue, and the area around the mouth becomes bluish to black, giving the impression the fish is wearing lipstick. Maximum length is over a foot.

rock beauty angelfish


To misquote the Melancholy Dane, “Aye, there’s the rub!” (What was the point in my having studied English all those years in college if I can’t draw upon ol’ Bill Shakespeare from time to time?) The rock beauty’s natural diet consists largely of sponges along with other benthic invertebrates and algae. It rarely takes to prepared aquarium fare. That means, unless they’re somehow provided a steady supply of natural food items, most specimens are doomed to die in captivity.

There are foods specially formulated for marine angels that contain sponge and balanced diets, and some captive specimens may take to them, possibly along with algae and meaty offerings, but again, this species’ record with respect to captive feeding is very poor.


If I were to attempt this species (not a risk I’m prepared to take despite my fascination), I wouldn’t try to keep it in a tank any smaller than a few hundred gallons and I would make sure it was a well-established system with plenty of live rock, providing opportunities for foraging/grazing on natural benthic food items to supplement whatever I could get the specimen to accept in the form of prepared foods.

A juvenile Rock Beauty foraging in the wild

A juvenile Rock Beauty foraging in the wild


H. tricolor tends to be more shy and skittish than some of its congeners, so aggressive tankmates are best avoided. I’d leave out other angels, including conspecifics, as well as similar-looking heterospecifics.

I wouldn’t really consider this species reef-friendly, as it will likely nip at a variety of sessile invertebrates, though it might work with caution in a larger system where it can’t focus too much of its attention on a small number of specimens.


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About Jeff Kurtz

Jeff Kurtz is the Co-founder/Editor of Saltwater Smarts, former Senior Consulting Editor for Tropical Fish Hobbyist Magazine, and the aquarist formerly known as “The Salt Creep.” He has been an aquarium hobbyist for over 30 years and is an avid scuba diver.


  1. Ah, the lure of the Rock Beauty (Holacanthus tricolor) has caught me too, Jeff. Keeping the Rock Beauty is a challenge for sure. I haven’t purchased one in many years for the very reasons you state in your article. There is one other observation I’d like to point out. In my experience with the Rock Beauty. Besides being shy and a finicky eater of captive food fare, they are also prone to diseases such as fungal infections and Ich (Cryptocaryon irritans). Treatment seldom works well as they do not take well to chemicals offered for treatment. Quarantine for 30 to 60 days before entering the display tank would be highly recommended. Of course I recommend QT for all fish.

    With the advancements in food items available to marine hobbyists, perhaps it’s time for me to give the Rock Beauty another go around. I do not recommend inexperienced hobbyists purchase the Rock Beauty for they, both the fish and the hobbyist, are not suited to success. Also, I totally agree with your statement, “I wouldn’t try to keep it in a tank any smaller than a few hundred gallons and I would make sure it was a well-established system with plenty of live rock, providing opportunities for foraging/grazing on natural benthic food items to supplement whatever I could get the specimen to accept in the form of prepared foods.”

    The reaction from new hobbyists surprises me when I explain to them that the food items offered to us at the LFS for our prized specimens are not, for the most part, found on the reef and therefore totally foreign to them. We literally have to entice the fish to try what we offer. Too many hobbyists take the easy way out with flake and pellet foods. Not the best offerings for sure.

    Thanks for another great article.

  2. Matt Bowers (Muttley000) says

    Nice article. I tried one of these 20 years ago, and it starved over the course of several weeks. I am glad info like this is avaliable now to prevent others from making the same mistake!

  3. Rick Dussault says

    Hi Jeff,
    Holacanthus tricolor hasn’t been of any challenge… at least for now. I have this nice fish in my tank for a year now. It was a little shy and ate only frozen food at first (for a few weeks). I got him at a size of about 3 inches. After a month or so it was eating almost anything I’d throw into the tank. From nori to flakes, frozen food to fresh mussels or shrimps. It’s, sorry, a real pig. Its mates are of different genus. The boss, Pomacanthus Imperator chases him sometime at night but nothing serious. Lamark’s and Centropyge argi are totally ignored. So is the Tridacnae gigas…for now. Paracanthurus Hepatus, a few chromis and a Mandarin are completing the list of fish have. The system is a 135g reef tank 54x24x24 with SPS only. The Rock Beauty is a very active fish and not considered easy to keep. I know it needs a varied diet and I try to feed a lot of diffrent foods each weeks. For now, I’m happy to succed into keeping that little fellow well fed, growing and top shape! 🙂

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