The only species of clownfish that I would consider keeping with seahorses are captive-bred-and-raised specimens of Amphiprion occelaris or Amphiprion percula. Those are the ever popular "Finding Nemo" look-alikes and they will often do well with seahorses providing you are willing to feed the ponies properly to assure that they get their fair share at mealtime.
Not all wrasse are compatible with seahorses, Joe. But many of the smaller reef-safe wrasse do well with domesticated seahorses and are colorful little fish that don’t mind chowing down on small bristleworms when the opportunity presents itself.
Here’s a list of compatible companions you can consider for seahorses (you will find a few wrasse species listed there that might fit the bill):
I have prepared a list of suitable fishes and invertebrates that generally make compatible tankmates for tropical seahorses below. Avoid fin nippers and aggressive, territorial fish that would be inclined to bully or physically abuse the seahorses, such as damsels, most clownfish, triggerfish, angels, puffers, cowfish and the like, as well as any predatory fishes that are large enough to swallow a seahorses, such as lionfish, anglers, sargassumfish, rays, large groupers and morays. For best results, other fishes that would not persecute the seahorses in any way should also generally be excluded because they are active, aggressive feeders that would out-compete the seahorses for food. This includes most butterflyfish, tangs, and most wrasse. Stinging animals like anemones and jellyfish are unsuitable, as are other predatory invertebrates such as lobsters, mantis shrimp, certain starfish and most crabs.
Clownfish meet many of the criteria for suitable tankmates, but should generally be regarded with caution (Giwojna, Feb. 2004). Most species, such as Tomato Clowns (Amphiprion frenatus), Maroon Clowns (Premnas biaculeatus), and Skunk Clownfish are surprisingly aggressive and territorial, and should be shunned on that basis. Others do best when keep with anemones, which are a threat to seahorses. All clownfish are prone to Brooklynella and Marine Velvet (Amyloodinium), and should be considered Ich (Cryptocaryon irritans) magnets as well (Giwojna, Feb. 2004). The only species I would recommend as companions for seahorses are Percula Clowns (Amphiprion percula) and False Percula Clownfish (A. ocellaris), and then only after a rigorous quarantine period (Giwojna, Feb. 2004). Captive-bred specimens are best and the cultured A. occelaris or percula are not normally territorial or aggressive toward seahorses.
In short, fishes that are suitable as companions for seahorses must be docile, nonaggressive specimens, which are fairly deliberate feeders that won’t out-compete them for food. Some good candidates include:
Anthias (assorted Mirolabrichthys, Pseudanthias, and Anthias sp.)
Firefish Goby (Nemateleotris magnifica)
Purple Firefish Goby (Nemateleotris decora)
Gobies (assorted small species)
Neon Goby (Gobiosoma oceanops)
Assessors (Assessor spp.)
Midas Blenny (Ecsenius midas)
High Hats (Equetus acuminatus)
Marine Betta (Calloplesiops altivelis) — small individuals only!
Banggai or Banner cardinals (Pterapogon kauderni)
Flame cardinals (Apogon pseudomaculatus)
Pajama cardinals (Apogon nematoptera)
Pipefishes (assorted small species)
Percula clownfish (Amphiprion percula)
False percula clownfish (Amphiprion ocellaris)
Royal Grammas (Gramma loreto)
Blackcap Basslets (Gramma melacara)
Green Chromis (Chromis viridis)
Blue Reef Chromis (Chromis cyaneus)
Longnose Hawkfish (Oxycirrhites typus)
Six Line Wrasse (Psuedocheilinus hexataenia)
Flasher Wrasse (Paracheilinus sp.)
Fairy Wrasse (Cirrhilabrus spp.)
Scooter Blennies (Synchiropus spp.)
Green Mandarin Goby or Dragonet (Pterosynchiropus splendidus)
Psychedelic Mandarin Goby or Dragonet (Pterosynchiropus picturatus)
Orchid Dottyback (Pseudochromis fridmani) – avoid other Pseudochromis species!
Mandarin gobies or dragonets (Pterosynchiropus spp.) are peaceful, deliberate feeders with brilliant colors that do well with seahorses and often even learn to accept frozen Mysis in time. But they are best reserved for very large, well-established aquaria with lots of live rock that supports an adequate population of copepods and amphipods to sustain them.
As far as invertebrates go, it’s important to avoid any stinging animals with powerful nematocysts. This means fire corals (Millepora spp.) and anemones should be excluded from the seahorse reef, and any corals with polyps that feel sticky to the touch should be used with discretion and only after careful planning. When a seahorse brushes up against them or attempts to perch on them, the nematocysts or stinging cells of these animals can penetrate the seahorse’s skin and damage its integument. Needless to say, this causes pain and discomfort and can leave the seahorse vulnerable to secondary bacterial and fungal infections, which may take hold at the site of injury. Short polyped stony (SPS) corals are generally fine, but large polyped stony (LPS) corals should be regarded with caution.
Likewise, it’s best for the seahorse keeper to avoid Tridacna clams and similar bivalve mollusks. Sooner or later a seahorse will perch on them with its tail between the valves and the clam’s powerful adductor muscle will clamp down on it like a vise. At best this will be a very stressful experience for the unfortunate seahorse, since it can be the devil’s own business trying to persuade the stubborn mollusk to release its struggling victim! At worst, it can result in serious injury or permanent damage to the seahorses tail (Giwojna, unpublished text).
Good inverts for seahorses include decorative cleaner shrimp like those listed below:
Peppermint Shrimp (Lysmata wurdemanni)
Scarlet Cleaner Shrimp or Skunk Cleaner Shrimp (Lysmata amboinensis)
Fire Shrimp (Lysmata debelius)
Harlequin Shrimp (Hymenocerus elegans and H. picta) – predatory on sea stars;
large ornamental snails (living sea shells) such as the following:
Tiger Cowry (Cypraea tigris)
Deer Cowry (Cypraea cervus)
Assorted Feather Dusters (Sabellastatre magnifica, Sabella sp.) whose colorful crowns resemble gaily-colored parasols.
As far as starfish go, it’s best to avoid a large predatory species such as chocolate chip starfish and African starfish (Protoreaster spp.). I would describe predatory sea stars such as these as "opportunistic omnivores," meaning that they are likely to eat any sessile or slow-moving animals that they can catch or overpower. For instance, I would not trust them with snails, clams, tunicates, soft corals and the like. Most fishes are far too fast and agile to be threatened by sea stars, but seahorses are sometimes an exception due to their sedentary lifestyle and habit of perching in one place for extended periods of time. What occasionally happens, in the confines of the aquarium, is that a predatory starfish may pin down the tail of a seahorse that was perched to the piece of coral or rock the starfish was climbing on, evert it’s stomach, and begin to digest that portion of the seahorse’s tail that is pinned beneath its body. That’s a real risk with large predatory species such as the beautiful Protoreaster starfish, which are surprisingly voracious and aggressive for an echinoderm.
But there are a number of colorful starfish that do well with seahorses. Any of the brightly colored Fromia or Linkia species would make good tankmates for seahorses. However, bear in mind that, like all echinoderms, seahorses are very sensitive to water quality and generally will not do well in a newly established aquarium. Wait until your seahorse tank is well-established and has had a chance to mature and stabilize before you try any starfish.
Two attractive species I can recommend are the Fromia Sea Star or Marbled Sea Star (Fromia monilis) and the Red Bali Starfish (Fromia milliporella), which are safe to keep seahorses. They are not nearly as delicate as the Linkia species and should do well in the tank such as you’re planning that has lots of live rock and optimum water quality, and are nonaggressive starfish that feed primarily on detritus and meiofauna on live rock and sandy substrates.
Snails, a few microhermit crabs, and cleaner shrimp are good choices as aquarium janitors and a seahorse tank. I prefer a cleanup crew consisting of a mixture of assorted snails and micro hermits (heavy on the snails but light on hermits) at a density of up to perhaps 1-2 janitors per gallon. The snail assortment may include bumble bee snails, trocha snails, margaritas, Astrea and Cerith snails, red foot Moon snails, etc., but especially Nassarius snails.
Nassarius snails are terrific detritivores and amazingly active for snails. They’ll bury themselves until they detect the scent of something edible, and then erupt from the sand and charge out to clean it up.
A varied assortment of snails is very desirable because different types of snails have different habits, seek out various microhabitats within the aquarium, and prefer to eat different things. Some are herbivores that feed on microalgae, and some of the herbivorous snails prefer to graze on it from the substrate, others like to to clean it from the rocks, and still others love to scrape algae off the aquarium glass. Furthermore, the different herbivorous snails tend to specialize on different types of microalgae and have definite preferences as to the types of algae they will eat, so it’s important to have a nice variety of snails that cover all the bases in that regard. It’s equally important to include some omnivorous snails in your assortment, which will go after meaty leftovers, along with the vegetarians. And you’ll want to have plenty of detritivores, too, which will feed on detritus and decaying organic matter in the aquarium
For best results, Astrea sp. snails should go in the tank as soon as the ammonia and nitrite levels are down to zero in order to keep nuisance algae from gaining a foothold in your tank. Introduced as soon as possible to a new aquarium, that has reached this cycling phase, Astrea snails effectively limit the development of all microalgae. In other words, they are good at eating diatoms, but will consume red slime and green algae as well.
But you must avoid predatory snails such as tulip snails, horse conchs, crown snails (Melanogena corona), and the venomous cone snails (Conus spp.), which can kill a human with a single sting from their harpoon like radula. Tulip snails, horse conchs, and crown conchs will hunt down and eat the other snails in your cleanup crew, whereas cone snails prey on small fishes in addition to presenting a deadly hazard to the aquarist.
For hermits, I like a combination of Dwarf Blue-leg (Clibanarius tricolor), Left-handed (Calcinus laevimanus), Mexican Red Legged Hermits (Clibanarius digueti) and above all, Scarlet Reef hermit crabs (Paguristes cadenati), which are my personal favorites.
The Scarlet Reef Hermit Crab (Paguristes cadenati) is a colorful micro-hermit that’s a harmless herbivore. So cannibalism isn’t a concern at all for these fellows, nor are they likely to develop a taste for escargot. As hermits go, most of the time the Scarlet Reefs are perfect little gentleman and attractive to boot. I even use them in my dwarf seahorse tanks. Best of all, they eat all kinds of algae, including nuisance algae such as red, green and brown slimes, as well as green hair algae.
If you’re going to have any hermits, stick with species like the above, which are known as micro hermits because they start out tiny and stay small. Avoid Anomura species of hermit crabs no matter how small they are, however, because they will kill Astraea snails to obtain their shells.
A mixture of the snails and micro hermits we have discussed will provide a very good balance of herbivores, omnivores, and detritivores that are all active scavengers and completely compatible with seahorses. They will clean up meatier leftovers such as frozen Mysis as well as helping to control nuisance algae.
With regard to the hermit crabs, there are a couple of other possible risks you should be aware of aside from the possibilities that the hermits could grow a large enough to be a threat to the seahorses.
For example, sometimes it works the other way around. Micro-hermit crabs are generally entertaining additions to an aquarium that do a great job as scavengers and get along great with seahorses, but over the years, I’ve had a few seahorses that were confirmed crab killers. These particular ponies were persistent hermit crab predators that specialized in plucking the hermits out of their shells and attacking their soft, unprotected abdomens, and they honed their skullduggery to a fine art. They were experts at extricating the crabs and would eat only their fleshy abdomens and discard the rest. Mind you, that was only a few individuals out of a great many Hippocampines, but I could never keep hermit crabs in the same tank with those specific seahorses.
On the other hand, sometimes it’s the micro-hermits that are the troublemakers. Most of the time, they coexist perfectly well with their fellow janitors in the cleanup crew. But I’ve had more than a few tiny hermits with a taste for escargot that persecuted snails mercilessly. These cold-blooded little assassins would kill the snails in order to appropriate their shells. Once they had dined on the former occupant, they would take up residence in their victim’s cleaned-out shell! It soon became clear that these killer crabs were driven not by hunger, but by the need for a new domicile. Once I realized they were house-hunting, I found I could curb their depredations but providing an assortment of small, empty seashells for the hermits to use. Colorful Nerite shells are ideal for this.
After the tank has been up and running for several months, you can add a few large Peppermint Shrimp (Lysmata wurdemanni) and/or Scarlet Cleaner Shrimp or Skunk Cleaner Shrimp (Lysmata amboinensis) to complete your cleanup crew and add a touch of color and activity to the tank.
Peppermint shrimp (Lysmata wurdemanni) are a favorite with seahorse keepers because they eat Aiptasia rock anemones, and both the peppermints and Scarlet cleaner shrimp (Lysmata amboinensis) will perform another useful service by grooming the seahorses and cleaning them of ectoparasites. As an added bonus, they reproduce regularly in the aquarium, producing swarms of larval nauplii that the seahorses love to eat.
Just remember, it is important to select the largest possible cleaner shrimp for your seahorse tank(s). Seahorses will actively hunt small cleaner shrimp and they are quite capable of killing shrimp that are far too big to swallow whole, so the cleaners need to be large enough that they are not regarded as potential prey.
Another thing to keep in mind when introducing cleaner shrimp to your aquarium is that they are more sensitive to water quality and rapid changes in pH, temperature, or salinity than fishes are, meaning the shrimp need to be acclimated more carefully and gradually. Whereas drip acclimation should be avoided for seahorses that have been on the shipping bag for 24 hours or more, it is the perfect way to acclimate delicate shrimp from your LFS. They will do best it drip acclimated to the new aquarium over a period of several hours to allow them to adjust to any differences in the water parameters very gradually.
Shrimp that are introduced to a new aquarium too abruptly will not flourish and are liable to die within a day or two from the stress of acclimation, unable to adjust to any significant differences in pH or salinity, or they simply fail to thrive and expire a week or two later for no apparent reason. If the shock is too great, they will autotomize, dropping legs, claws and/or antennae immediately upon being introduced to the new aquarium conditions.
By no means is this intended to be a comprehensive compilation. It is intended merely to give the hobbyist an idea of the types of fishes and inverts that generally make suitable tankmates for seahorses. But there are many more seahorse-safe fish and invertebrates that could have been added to the list, and no doubt many aquarists would disagree about some of the species that have been included.
For more information on seahorse-safe tankmates, see Will Wooten’s online Compatibility Guide at the following URL:
Be that as it may, there are three precautions that should always be observed when contemplating keeping seahorses with other fishes:
(1) All fishes that are intended as tankmates for seahorses MUST be quarantined first without exception, unless they are captive-bred-and-raised animals obtained from a high-health aquaculture facility. Any fish you bring home from your LFS is a potential disease vector for all manner of nasty pathogens and parasites, and you need to take every possible precaution to prevent these from being introduced to your display tank.
(2) If you are new to seahorses, you will be much better off sticking to a species tank rather than attempting to keep them in a mixed community. Beginners are well advised to keep things as simple as possible while they learn the ropes, and introducing other fishes and invertebrates tankmates complicates feeding and carries new risks that inexperienced seahorse keepers are ill-equipped to cope with. Get some firsthand experience with seahorses before you consider adding any tankmates other than a cleanup crew.
(3) You must be willing to feed the seahorses properly when keeping them with other fishes in order to assure that the seahorses get enough to eat, as discussed below:
Feeding Seahorses in the Community Tank
When keeping seahorses in an appropriately elaborate environment, it is imperative that you feed them properly! Domesticated seahorses thrive on enriched frozen Mysis as their staple, everyday diet. But the worst thing you can do when feeding the seahorses in a intricate reef or live rock environment is to scatter a handful of frozen Mysis throughout the tank to be dispersed by the currents and hope that the hungry horses can track it all down. Inevitably some of the frozen food will be swept away and lodge in isolated nooks and crannies where the seahorses cannot get it (Giwojna, 2005). There it will begin to decompose and degrade the water quality, which is why ammonia spikes are common after a heavy feeding. Or it may be wafted out into the open again later on and eaten after it has begun to spoil. Either outcome can have dire consequences (Giwojna, 2005).
The best way to avoid such problems is to target feed your seahorses or set up a feeding station for them. See my online article in Conscientious Aquarist for a detailed discussion explaining exactly how to set up a feeding station and train your seahorses to use it:
Click here: Seahorse Feeders
Personally, I prefer to target feed my seahorses instead. The individual personalities of seahorses naturally extend to their feeding habits. Some are aggressive feeders that will boldly snatch food from your fingers, while some are shy and secretive, feeding only when they think they’re not being observed. Some like to slurp up Mysis while it’s swirling through the water column, and some will only take Mysis off the bottom of the tank. Some are voracious pigs that greedily scarf up everything in sight, and some are slow, deliberate feeders that painstakingly examine every morsel of Mysis before they accept or reject it. Some eat like horses and some eat like birds. So how does the seahorse keeper make sure all his charges are getting enough to eat at mealtime? How does the hobbyist keep the aggressive eaters from scarfing up all the mouth-watering Mysis before the slower feeders get their fair share? And how can you keep active fishes and inverts with seahorses without the faster fishes gobbling up all the goodies before the slowpoke seahorses can grab a mouthful?
Target feeding is the answer. Target feeding just means offering a single piece of Mysis to one particular seahorse, and then watching to see whether or not the ‘horse you targeted actually eats the shrimp. Feeding each of your seahorses in turn that way makes it easy to keep track of exactly how much each of your specimens is eating.
There are many different ways to target feed seahorses. Most methods involve using a long utensil of some sort to wave the Mysis temptingly in front of the chosen seahorse; once you’re sure this has attracted his interest, the Mysis is released so it drifts down enticingly right before the seahorse’s snout. Most of the time, the seahorse will snatch it up as it drifts by or snap it up as soon as it hits the bottom.
A great number of utensils work well for target feeding. I’ve seen hobbyists use everything from chopsticks to extra long tweezers and hemostats or forceps to homemade pipettes fashioned from a length of rigid plastic tubing. As for myself, I prefer handfeeding when I target feed a particular seahorse.
But no doubt the all-time favorite implement for target feeding seahorses is the old-fashioned turkey baster. The old-fashioned ones with the glass barrels work best because the seahorses can see the Mysis inside the baster all the way as it moves down the barrel and out the tip. By exerting just the right amount of pressure on the bulb, great precision is possible when target feeding with a turkey baster. By squeezing and releasing the bulb ever so slightly, a skillful target feeder can keep a piece of Mysis dancing at the very tip of the baster indefinitely, and hold the tempting morsel right in front of the seahorse’s mouth as long as necessary. Or if the seahorse rejects the Mysis the first time it drifts by, a baster makes it easy to deftly suck up the shrimp from the bottom so it can be offered to the target again. In the same way, the baster makes it a simple matter to clean any remaining leftovers after a feeding session. (You’ll quickly discover the feeding tube is also indispensable for tapping away pesky fish and invertebrates that threaten to steal the tempting tidbit before an indecisive seahorse can snatch it up. And it’s great for tapping on the cover to ringing the dinner bell and summon the diners for their gourmet feast!)
In short, target feeding allows the hobbyist to assure that each of his seahorses gets enough to eat without overfeeding or underfeeding the tank. And it makes it possible to keep seahorses in a community tank with more active fishes that would ordinarily out-compete them for food, since the aquarist can personally deliver each mouthful to the seahorses while keeping more aggressive specimens at bay.
The key to keeping active specimens like firefish or cleaner shrimp successfully with seahorses is to feed the other fish and inverts with standard, off-the-shelf aquarium foods first, and once they’ve had their fill, then target feed the seahorses.
Here’s hoping you find just the right tankmates for your needs and Interests, Big Joe!