Flowerhorn Origins, Care, Breeding, & Controversy

The internet is near-bursting with mysteries, misinformation, and controversy about flowerhorns. Even their care requirements seem like they’re up for a not-so-friendly debate. And the truth is… we don’t really know. Mostly because flowerhorn secrets are so closely guarded by their creators.

Even the hobbyists that do know a thing or two about flowerhorns don’t know all there is to know. These fish are more art than science, I guess. I know, I know…

But that’s not to say we don’t know anything about them, just that what we do know seems to be based on nebulous numbers and anecdotal information supplied by enthusiasts. On top of that, since they’re a hybrid, their genes are constantly in flux, so there’s a considerable number of variables. So, without further ado, here’s what we do know about keeping, feeding, and breeding flowerhorns…

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Table of contents

Do All Flowerhorns Get A Hump?

Not all, no. For starters, females typically don’t develop a hump (or a kok,) but most males do. With that said, there are always exceptions to this rule and not all male flowerhorns develop a hump and not all females don’t. Genetics and care play a large role in the prominence of the kok, but most males will develop theirs by the time they’re 9″ – 10″ long. Before then, they often look more like females.

Adding to the confusion – as if it weren’t already up there – there are several classes of koks based on the shape, size, and density:

What Fish Make A Flowerhorn?

Flowerhorns are a hybrid that was cooked up in Chinese tanks some time in the 90’s. (Is it really almost 30 years later?!) There are at least six potential fish that might make up what we know today as flowerhorns. Though to what degrees – if any at all – each of these species played, no one seems to know. And those who do know aren’t saying, not that I can blame them since these fish have generated millions.

Red devil (Amphilophus labiatus), redheaded cichlid (Paraneetroplus synspilus) midas cichlid (Amphilophus citrinellus), red terror (Cichlasoma festae), trimac (Cichlasoma trimaculatum), and parrot fish are all listed as possible crosses that formed flowerhorns.

Parrot fish have a good deal of debatable genetics in their own right since they’re also a hybrid. Some claim they come from the exact same ancestors as the flowerhorn (doubtful at best) and others claim convicts, jack dempseys, and even goldfish had a role in the creation of parrot fish. So the number of potential candidates could jump if you want to include possible crosses that resulted in parrot fish. And, even still, there is quite a bit of debate about the six species – well, five and a hybrid.

Some suggest a mix of Vejia species aside from the readheaded cichlid (there are seven other contenders.) Others say Herichthys carpintis was a part of the project. There are also claims that different flowerhorn strains all come from different species crosses, while others claim the original flowerhorn strain was created first and then made into different color morphs (which is highly unlikely.)

At the end of the day, speculation and well-aimed guesses are the best we can manage. But to most who see them, readheads and trimacs seem like an obvious starting point.

Flowerhorn Controversy

In the world of flowerhorns you have lovers against haters, haters against haters, lovers against lovers – lines are being drawn in the sand every which way. So let’s dig into these battle lines and play a little devil’s advocate – just for fun – shall we?

Loss Of Genetic Integrity

Against: The loss of genetic integrity is a serious blight for some species. Take most apistogrammas, for example, or the very common jewel cichlids, or bumble bee gobies. The preservation of genetic integrity is important.

The issue for flowerhorns lies in the fact that some low-grade flowerhorns could be mistaken for (and misold as) a trimac and could pollute the real line, turning breeding lines into a hodgepodge. People paying good money for a rare fish could be seriously duped and their breeding program screwed.

For: Betta splendens is often hybridized with other betta species. Quite regularly, in fact, and they’re sold as b. splendens and not a hybrid. On top of that, we see them wreaking havoc on wild populations due to escapees as well. Odd that no one seems to be in arms over bettas. Bettas are actively destroying the genetic integrity of wild and captive species due to humans being just as careless with them as flowerhorns. But, hey, whatever.

They Escape Into The Wild

Against: The “wild” flowerhorns pose a very real – and serious – risk to wiping out species of fish in the wild since they’re an invasive species in more than one country.

For: Plenty of true species of fish pose a risk to wiping out fragile and endangered local wildlife (eh-hem; guppies, oscars, snakeheads, talapia, goldfish, and betta splendens just being a few.) But what really seems to raise hackles on this topic is that a man-made fish can pose that issue as well.

Frankensteins

Frankenstein – if you didn’t know – was the name of the creator of the monster, not the monster’s name. And that’s, more or less, what we’re talking about here. Those folks at home who want to get purebred trimacs, red terrors, and redheaded cichlids to mash up their own monster fish hybrid.

So what’s the issue?

Against: Those fish are friggin hard to get and people are downright pissed that folks are snapping them up to do the monster mash with. It seems like an injustice to the species – and the hobby – to get a hard to find fish just to make a monstrosity. On top of that, the flowerhorn community is – seemingly – against them as well. Are they even “real” flowerhorns? What’s the point? What are you going to do with all those useless fry? This is why people hate flowerhorns. That sort of thing.

For: Is this not what the hobby was for? To breed, to play, to tinker? As long as you’re breeding and caring for all fish responsibly and ethically, who cares? Why drive people out of the hobby because you disagree with them?

You’re Missing Out On “Real Fish”

Against: With thousand – literally – thousands of fish to choose from, why waste the time, energy, space, and cash on an expensive hybrid when you could get the real thing?

For:

Seriously though, who cares?

Flowerhorn Aquarium Care

Everything in the world of flowerhorns seems like it’s up for debate. Unfortunately, this includes best care practices. Though the general consensus for care requirements based on their potential lineage looks something like:

And it’s worth noting that some keepers say they’re dangerous. I would be more concerned about losing a digit to a fish like a dovii (wolf cichlid) peacock bass (Cichla ocellaris), or a jag (jaguar cichlid) than these lightweights.

Still, flowerhorns have sharp teeth, plenty of muscle, and grow to a size of 12″. If you would be worried by an oscar, you should be concerned about the much more aggressive and sharp-toothed flowerhorn. Using your best judgment, wearing gloves, and making sure your fingers don’t look like a treat is the best bit of advice I can give if you want to try to get your hands in their space.

Tank Specs

Most keepers suggest something like a 50-gallon or a 55-gallon tank for a single fish, though 75-gallon is much better, and 150-gallon is the lowest suggested for a pair as they can be quite aggressive and have large spawns. Flowerhorn aficionados suggest something closer to 150 gallons as a tank size for one fish.

You’ll want to make sure, much like with oscars, you fish proof your tank. They can easily damage equipment, break the glass, or hurt themselves. Many keepers report equipment harm being a flowerhorn’s first love. They like their tanks quite warm, again, how warm is up for debate. But you’ll still likely need a heater – better yet – an inline heater or one with a protective case around it. You can DIY your own protective case using PVC if you want.

Stocking Flowerhorns

It’s always safer with these guys to go without tank mates – even a fellow flowerhorn. Unless, of course, you’re planning on breeding them, I would generally advise that you keep your flowerhorn cichlid solo. They’re so aggressive that deaths and injuries to themselves or their tankmates is more a matter of when than if.

Decor

Most people chose to forego decor in flowerhorn tanks, but they seem to not care, either way.

There are a few theories with non hybrid fish that they prefer decor that mimics their natural habitat – even if they haven’t seen it. This is also another area of confusion surrounding the flowerhorn. I have hear some theories that that’s why they don’t care about decor, or suggestions that it should be Central American themed, but they really do seem fine in an empty tank by themselves.

Best Plants For Flowerhorns

Flowerhorns, like most cichlids, have a tendency to destroy plants. There are a few hardy, durable plants that might survive their wrath. In general, look for plants that can be superglued or tied down and it would probably be in your best interest if these plants were cheap and easy to come by as well. Generally, slow-growing and tough-leafed plants will fare best. But, even still, if a flowerhorn doesn’t want plants there won’t be any (and they typically don’t.)

Anubias (Anubias barteri)

Java Moss

Lighting & Filtration

Lighting doesn’t seem to matter a ton to flowerhorns, though they do prefer dimmer to brighter. But what fish doesn’t?

Filtration, however, is more important. Most flowerhorns rip apart sponges, so sponge filters and sponge intake covers are more likely than not out of the question unless it’s a breeding tank and it’s temporary. Internal filters can easily get broken or moved to the wrong spot, so they’re a possibility, but not an ideal one. HOBs generally don’t have the turn over rate you’d need to keep a flowerhorn’s tank clean, and if you go larger than 50 gallons, you’re probably going to have a tough time find an effective HOB.

So that really only leaves us with one suitable option in most situations. Of course you can do a DIY filter, a sump, a refugium, etc., but they all cost more in both time, money, and expertise to set up and run. They’re also more when it comes to maintenance and the flexibility is usually lacking once you set it up unless you think ahead.

For flowerhorns – and most large cichlids, really – this is where canister filters really shine. They usually provide biological, mechanical, and chemical filtration all in one unit, they produce a good deal of water movement and surface agitation to prevent stagnant water and – best of all – they’re easy to maintain and hard for flowerhorns to ruin. I say hard, not impossible though.

You’re likely going to want a filter with a turn over rate of five to seven times per hour. Most canister filters have an adjustable flow, so if you’re not sure, go with the higher number and slow the flow down if needed. If you’re unsure how to calculate turn over rate, multiply the size of your tank (in gallons) by seven. You can, of course, do a lower number, but seven is a safe bet.

The number you come up with is the number of gallons the filter should be able to handle per hour. (Ex: 50 gallon with a 7x hourly turnover rate would need a filter that could handle 350 gallons per hour.)

Again, most of them are adjustable, and I would advise you go too big versus too small. The first is a much easier – and cheaper! – fix than the other. If you’re lost on the best canister filters for the job, I have some below for you.

Water Care

Even with a good filter, expect to do large, frequent water changes on your flowerhorn tank. Depending on the size of the tank, the size of the fish, your filtration, and how much you feed them, you’ll likely be doing at least one 25% water change weekly.

If you can, two weekly water changes of 50% are even better. If this sounds like a lot of water, that’s because it is. On top of that, I suggest you clean out your filter at least weekly. The Python makes this task much easier. (Have you ever lugged 50+ gallons of water in buckets every week?) I have. Huge pain!

Large cichlids like flowerhorns are incredibly susceptible to hole in the head disease. Which is exactly what it sounds like. I cover this in a bit more detail below, but a lack of clean water is the largest contributing factor to this condition. They can also easily get fungus and fin or body rot – which are all water quality related as well. Be sure to give your flowerhorn as much clean water as you possibly can without stressing them – or yourself – out.

Aside from a somewhat heavy water change schedule, you’re probably going to want to buy water conditioner in a larger size than most people. Flowerhorns are also susceptible to quite a few common diseases, the medications for those are listed below as well so you can make yourself a flowerhorn first aid kit.

Feeding Flowerhorns

Feeding a flowerhorn is – as I’ve come to expect – another minefield. It’s not that the fish are picky, it’s just that everyone has a different opinion on what they should be fed. Literally everyone.

Most of the suggested products have a hefty dose of astaxanthin (a red carotenoid), which isn’t surprising given their coloration. Some of the more niche (and, admittedly, unusual products) capitalize on owners’ desire for a larger hump, claiming high-protein foods will do the trick. This is not only unfounded but also unlikely since the majority of the kok is comprised of water and fat.

Given that fowerhorns are prone to obesity, a diet with large doses of fat should be avoided as well. In general, flowerhorns do well on most dried, freeze-dried, and frozen omnivore diets. Though flowerhorns caught in the wild rarely have any plant matter in their system, so maybe take omnivore with a grain of salt.

The general consensus, however, is that you shouldn’t feed your flowerhorn just one food. Not surprising, most fish don’t thrive off of just one type of food. You’re probably going to want three to four types for the best growth and rotate them. With that said, more is usually better, so go nuts if you can and feel inclined!

Flowerhorn Diseases

Man, flowerhorns are weird. Some people say they’re basically bulletproof and can get lost in the mail for a month and still show up alive. Others say changing too much of their water can easily kill them. Some say some strains are more susceptible to certain diseases than others, some are hardier strains than others. Some people say that has nothing to do with it and it’s where you get them from because of the different germs in the water.

Writing a solid, practical, and complete guide on a fish that has so many things up in the air – in part because it’s a hybrid – makes things difficult for both of us. There were, however, a few diseases that – when diseases did pop up – seemed to pop up again and again.

Hole In The Head (HITH) or Head & Lateral Line Erosion (HLLE)

Fin Rot & Tail Rot

Bloat

Ich (White Spot Disease)

Flowerhorn Tank Mates

I suggest keeping your flowerhorn solo – strongly advise, really. Even if you do everything right, including getting very lucky and getting compatible fish and introducing them at a young age, even babies can get feisty and start a life-long war.

But if you’re determined to keep yours with other fish, there are a few things to keep in mind when looking at tank mates. First, the size of the other fish. You’ll want them to be roughly the same size or slightly larger than your flowerhorn once they’re full-grown. If they’re too much larger, your flowerhorn could become a snack if (when) it decides to pick a fight with a larger fish. If they’re smaller, obviously they could become a snack or be bullied easier.

Speaking of fights, you’ll want to think about the aggression level of the other fish. If the flowerhorn is likely to be the aggressor, you’ll want the other fish to be larger than the flowerhorn and introduced to the tank first to give them the most confidence (and knock the flowerhorn’s a bit) to prevent stress on the less aggressive fish.

One last note on tank mates: you’ll want to make sure you have enough space for four or five fish (including the flowerhorn) to spread aggression around a bit. Any less and you run the risk of giving the flowerhorn a single target, and any more you run the risk of too much going on for the flowerhorn. This means you should be looking at tanks in the 150-gallon and up range if you’re thinking about tank mates.

With those final words, here are some possible tank mates that probably won’t work out but offer you a decent enough chance of success. And, as always, this is not a definitive list:

I would suggest avoiding most other large cichlids with these guys. Flowerhorns can rehybridize with dovii, jags, oscars, jack dempseys, and most of the other large and aggressive South/Central American cichlids. The cichlids they can’t hybridize with seem to not get along great with them.

You can, of course, try to keep your flowerhorn with a flowerhorn of the opposite sex, but I’m not going to cover that here, I’ll cover that below in the breeding section. If you don’t want fry, this is something you shouldn’t attempt. They may live together their whole life and never get on well enough to breed, but chances are good they’ll eventually relent – even if it’s only once.

Breeding Flowerhorn

There seems to be a wave of blogs claiming that breeding flowerhorns is easy, raising the fry is easy, selling them is easy. Oh, it’s all just like totally super easy, don’t even worry about it and you’ll make like super good money too.

Sure, getting them to breed can be easy if you get compatible fish and introduce them correctly – but getting fry out of the deal? Little bit tougher. Okay, but selling these guys is easy, right?

Even if you do get a fertile pair, getting rid of the fry can be a challenge. Not only do most of them not come out at sale-quality (so you’ll likely need to cull them or have tons of tanks at the ready for unsellable ones), but there seems to always be more sellers than buyers. Most fish store – as a bonus – won’t touch these guys, either. Not to mention your start up cost won’t be cheap.

In short: breed at your own peril and no, you’re not gonna cash in and quit your job.

Spawning

They’re hybrids, so the male is usually infertile. There are some theories – most of which are ancedotal – that say the “pure” flowerhorns have an easier time being bred since they’re not “re-hybridized.” Some say Thai imports have a lower chance of being fertile or that their eye color correlates to their fertility. None of it is true. It’s basically a hope and prayer on their genes being lined up correctly.

Getting a pair to spawn is easy enough. You’ll want to start with two adults of the opposite sex. How quickly they develop to sexual maturity depends heavily on the line they come from. It can take a few months or a few years depending on their genetics. Ten months is the lowest I’d say is mature, three years is about the max.

Getting a male and female is easy though since sexing flowerhorns is pretty straightforward if they’re fully grown. If they’re not, you might have to resort to venting them.

You can introduce them into a 150-gallon tank through a mesh divider. Sometimes you can release them after a few days, sometimes a few weeks – it depends on the fish’s personalities. Once you release them, the first few weeks will usually be filled with lip locking and body slapping to establish dominance.

Once they sort out who’s the alpha and where each fish’s lines are drawn, they’ll usually get along fine. I’d still keep the divider handy just in case. From there, it’s taking great care of them and offering a suitable spot for them to lay eggs. And then you wait. Might take days, months, years or – very possibly – never for them to spawn. A lot of variables here, I know.

Once they do start to spawn, here’s what it looks like:

Eggs & Fry Care

Once they lay their eggs, you’ll usually be able to tell within 12 hours if they’re infertile or not. It’s a good idea to take the parents out around this time as well and move them into a new home – though some parents do fine raising the fry, so I’d give them a few tries before you do this. If they are infertile, they eggs will turn white and fuzzy.

Most fish’s first spawns are infertile, however. I would give it maybe three or four tries before you label them as infertile. It’s rare, but not unheard of, for females to be infertile as well. If they are, most owners report them being unable to lay eggs at all.

If the eggs are fertile, they’ll hatch in roughly 48 hours, but they won’t be fully hatched and free-swimming until about 5 days after they’ve been fertilized. You don’t need to do anything in this time, but once they start swimming you’ll need a large batch of baby brine shrimp on hand. They grow quickly a eat a ton, so be prepared for a good deal of water changes as well.

By two weeks or so, they’ll be ready to eat daphnia, so make sure you have a 50-gallon culture (or so) ready to go before you start breeding them. You may want to consider a few large cultures just to be sure. By a month, they should be ready to start taking pellets and other prepared foods.

Again. If you even get lucky enough to get a fertile pair.

To put it into perspective how difficult it is to get a fertile breeding pair, my local store has a pair on display with fry. They were offer $5,000 for the pair and they flat out refused to sell. Period. Given that only 10% or so of the fry will be sellable, this should tell you how difficult a fertile pair is to obtain.

So if you do see a flowerhorn breeding pair for sale where the seller claims that they’re viable and they’re great parents, be skeptical. Most people don’t sell proven pairs. Even a proven pair of discus is somewhere to the tune of $500 – $1,000 – without the proof of fertility, mind you.

Flowerhorn Types

So there are two basic types of names flowerhorns get. One for their lineage (King kamfa, kamfa, etc.) and one for their coloration and pattern (fader, golde base, Thai silk, etc.) With how quickly these new variatns pop up, go out of style, get reclassified, duped, and then get debated, I thought it was best to not even attempt it here.

There are a ton of nuances to these guys and I felt that by trying to cram it into one section of this post, I’d be doing it a massive injustice. Your best bet is to hit some forums on flowerhorns and do some reading and posting if you want to know about the different types.

Further Reading & Sources

Research Gate: Alien attack: trophic interactions of flowerhorn cichlids with endemics of ancient Lake Matano (Sulawesi, Indonesia)
KMU: Effects of dried fairy shrimp Streptocephalus sirindhornae meal on pigmentation and carotenoid deposition in flowerhorn cichlid; Amphilophus citrinellus (Gunther, 1864) € 3 Cichlasoma trimaculatum (Gunther, 1867)