It is a bad idea to enter the aquakeeping hobby on a lark. Not only is this a recipe for any of various easily-avoided mistakes that beginners make, but it encourages a cavalier attitude about one’s new pets. It is easy to treat fish and other small-animal pets as easily replaced decorative accents rather than animals with their own needs, behaviors, and beautiful uniqueness, especially since relatively few fish respond well to attempts to physically interact with them.
I started on the path to fishkeeping as a precocious child, and my parents and other adult models were not themselves hobbyists. What I learned about the best practices for populating and maintaining an aquarium, I learned by reading every fish book I could find…and by trial and error.
There were a lot of errors.
Every fish that perished prematurely under my care stung my precocious heart. I felt affection for every individual fish, even if I couldn’t tell them apart or if I replaced them quickly. For every one of them, seeing them sicken and die as a result of something I did felt like a crime I was committing not just against them, but against their whole kind. This idea stuck in my mind, each failed effort seeming like an un-redressed wrong as well as an unsolved problem. I convinced myself over the years that I could assuage my conscience by revisiting each species and giving it, with that later effort, a home in which it could thrive. There is no possibility of effecting restitution for the fish I killed long ago with my overzealous and poorly-informed attempts, but I can still do right by others. Even if that reasoning is decidedly irrational, these stories may spare other aquakeepers from making the same mistakes and other fish from these often-gruesome fates.
Some of my favorite youthful memories are of fishing in rivers and lakes in New Jersey. Most of those are of collecting snails, crayfish, and Gambusias with nets, and these held no particular challenge once they came home with me and my family. On one occasion, we tried rod-and-reel fishing in a different park, and this got us a whole new kind of fish to observe: sunfish.
Sunfish (Lepomis; Centrarchidae) are, visually, temperate North America’s answer to South America’s and Africa’s cichlids. Visually stunning and very much on the large side as aquarium fish go, they are more popular as such in Europe than in North America. In this region, they are best known as game fish that put up a good fight for their size, and as food.
The day I brought home three sunfish of probably-mixed species, I did not know what I was getting into at all. I had a then-empty 20-gallon tank inherited from my grandmother, whose goldfish had all died for the last time, and I put those three sunfish and their new tankmate (more on that one later) all in there together. I didn’t know that sunfish are viciously territorial and that the healthiest one would keep the others from getting their fair share of the feeder minnows, and I didn’t know that they would do little more than hang still in their respective corners without a great deal more space and more cover. Eventually, there was only one sunfish, which lasted long enough that I eventually rehomed it to my elementary-school science teacher along with the family parakeet shortly before we moved to Miami. On the bright side, I was not yet in the habit of heating my aquaria, so I didn’t add to their troubles by giving them water that was far too warm.
The plan: I hope, in the fullness of time, to be able to build a large (~70+gal) cold-water aquarium, which will be home to sunfish, one or more species of mid-sized cyprinids like creek chubs or larger minnows, manageably-sized temperate catfish like madtoms, freshwater sculpins, and because I probably won’t have more than one large tank specifically earmarked for temperate species, a European weather loach. There will be wood, cold-water plants that are tough enough to withstand whatever destruction those fish might inflict, a decent current, and room for territories. I’m also hoping, possibly separate from that, to try black-banded sunfish, a species that is of a much more manageable size but that I’ve never seen for sale in a North American pet store.
The fourth fish in that sunfish haul was not a sunfish at all, and it was years before I figured out what the heck the yellow beast with brown spots I had brought home was. It died during the first night from bullying by the sunfish, transit stress, and probably cold, but the confusion and the image stayed with me long enough that I eventually connected it to an image in an aquarium book and to the results of some image searches. The “bushfish” are a group of fish kin to bettas, gouramis, and the famous climbing perch of southeast Asia, found in Africa and rarely seen in the North American aquarium trade. The one I caught was almost certainly one that had been dumped by someone no longer interested in caring for it, a grotesque response to losing interest in any non-native animal. Though hardy enough to, apparently, survive in the wild of a New Jersey park in summer long enough to be caught by an amateur angler, Ctenopoma acutirostre do not assert themselves against large, territorial fish like sunfish and cichlids; are tropical fish from the Congo basin rather than temperate fish from New Jersey; and require hiding places such as plants and driftwood to feel secure, so the place where that fish spent its last night was FAR from ideal.
The plan: Another themed tank idea I’d someday like to put together is a central-African-themed tank, featuring Ctenopoma, African freshwater butterflyfish, Congo tetras, upside-down catfish, and similar creatures that get far less attention than they deserve in most aquarist circles. I might even sport for a bichir and/or elephantnose if they start small enough and the other fish start large enough.
Tire Track Eel
It will surprise no one, I’m sure, that from the youngest ages I made a beeline for the “miscellaneous” part of every pet store’s aquarium section. Goldfish and tetras are delightful creatures, but I had to grow into my fondness for these more “ordinary” fish. The ones in which I delighted from the first were always the difficult-to-categorize oddities that reinforced the sheer diversity of fish and which, adding to their mystique, showed up irregularly based on whatever the supplier managed to receive from wild-braving fisherfolk in their native lands. These tended to be expensive, though, so they rarely joined the more common beasts that did make it home with us. One oddity that I did get to take home was labeled “tire track eel,” whose odd proboscis and rich pattern intersected handily with a more modest price tag than the Congo puffer or Chaca catfish also in the store in that era. Instead, the eel-like creature buried itself in the gravel and stayed out of sight, except for sometimes its head, for the duration of its stay. Mom, during insomniac episodes, noticed it unearthing itself nightly, doing laps around the tank, and returning to burial, but the only activity I noticed during the day was one occasion when it wheedled its way into the interior of a tank decoration and didn’t come back out.
The creature’s name didn’t match any of the look-alike fish in my fish encyclopedia, which I might not have found so bothersome if I’d known then that it was written for a British rather than American audience. So, I failed to notice that, even if I never did figure out what species this animal was, I could at least recognize it as, most likely, a member of the Mastacembelidae or “spiny eels,” and treat it accordingly. Most mastacembelids are much larger than this creature ever got, but more than that, they are nocturnal, secretive, and usually predatory. Well-informed owners feed them in the dark because they simply do not come out for food otherwise and thus get out-competed by their diurnal tankmates. The fish’s nightly rounds were its sign that it was slowly starving, signs none of us in the house knew how to read. Eventually, the fish disappeared entirely, presumably wasted away inside its tank-decoration hideout. I should forgive myself for that child’s error, but I never have.
The plan: Most mastacembelids are aggressive toward their tankmates, grow quite large, can escape poorly-sealed tanks and die of desiccation, and have a habit of eating smaller fish. So, this is a family I will only revisit if I can find the smallest commonly available species, Mastacembelus circumcinctus, which is what my anomalous “tire track eel” probably was. A southeast-Asian-themed tank with danios, gouramis, and this creature would address many of my prior errors and be visually striking as well, while the larger species would need to be housed alone and be spectacular on their own. Either way, my next mastacembelid will have a better set of shelters and hideaways than that unfortunate victim, and it’s getting fed at night.
Another oddity from the Whiteway Pet Shop that joined us was a “freshwater sole.” That term is in quotes because only a handful of flatfish actually are freshwater fish, and they are outnumbered by brackish-water species that are sometimes found in adjacent freshwater environments. Often, only flatfish specialists can easily distinguish between the brackish and properly-freshwater varieties, and that’s if a particular batch isn’t itself a mix of species with different preferences. So, I do not know whether the flatfish I brought home that day appreciated the freshwater environment it received. I do know, now, that keeping such a fish on a gravel rather than sand substrate was cruel, because it was unable to bury itself and therefore spent the whole time trying to hide behind decorations and otherwise feeling very conspicuous. I also know, now, that flatfish are not particularly eager feeders and so don’t do well in tanks with a lot of food competition, and also that many never quite get the hang of prepared foods, even sinking pellets. So, my “freshwater sole” almost certainly perished scared, exposed, in osmotic shock, and very, very hungry.
The plan: My interest in brackish-water fish is real but limited. There are a lot of very cool brackish fish, but they are such a limited slice of the offerings in pet stores and fish wholesalers that I’ve been unable to will myself to focus on housing and caring for them specifically. If space permits, I might like to set up a tank with four-eyed fish, green puffers, and brackish flatfish—all fish that are severely under-served by attempts to keep them in fresh water but that aren’t so specialized that they can’t have tankmates. Alternately, I could make the concerted effort to find flatfish that are actually at home in freshwater conditions, and keep them with filter-feeding shrimp and other creatures that don’t seek the same food items I’d feed to the flatfish. And, of course, they get a sandy substrate.
Corydoras catfish are probably the most ordinary of the fish I’ve mistreated over the years. Even the goldfish with which I got my start were better off than the cories I excitedly added to my earliest attempts at tropical community tanks. I made two mistakes with these fascinating and adorable herd animals. I kept my first few in tanks with gravel, and I kept them alone. As I’ve mentioned before, Corydoras catfish and most of their Callichthyidae kin are schooling fish that do not behave naturally when kept without a group of their fellows, and my unfortunate pets were no exception. Also, I kept mine over gravel, which is not ideal for fish that like to sift through sand with delicate barbels. The mistake that weighs on me the most regarding cory cats, though, is the time that I used water that was too hot during a water change and killed two with heatstroke. That mistake, I have never repeated, and Father Dagon willing, I never will.
The plan: My current main display tank has Botia loaches and Synodontis catfish as its primary bottom-feeders and uses Flourite rather than sand, so cory catfish are not in the cards. (The botias would benefit from sand as well, but they don’t seem to mind the Flourite). I’d be delighted to house some with those freshwater soles from above and/or with other fish that benefit from sand or fit thematically with fish that do. For now, I’m keeping pygmy corydoras (Corydoras pygmaeus), which spend much more time in the middle of the tank rather than the bottom, co-school with my emerald-eye rasboras, and like to rest on the massive thicket of Valisneria that passes for my aquascaping. The larger, benthic cories and their Brochis, Dianema, and Aspidoras cousins are on my list for future efforts. Their peaceful, inoffensive nature means that few fish are unsuitable tankmates.
The term “hillstream loach” refers to a number of species of South and Southeast Asian loaches in several families, but today, it refers specifically to the sucker-bodied creatures of the genus Gastromyzon. Sporadically available, their weirdness immediately got this child’s attention, but they didn’t last long in my tank on the one occasion that I managed to convince Mom to let me bring one home. As it turns out, Gastromyzon loaches and their kin do not do well in environments that don’t resemble the highly oxygenated, fast-flowing rivers they naturally inhabit, and require both of those qualities to feel at home. Mine disappeared relatively quickly, presumably from hypoxia and then having their remains evaporated by various scavengers.
The plan: Because of the specialized tank needed to show these creatures at their best, I will almost certainly avoid them in the future. They’re beautiful and interesting, but not interesting enough for an elaborate setup that they cannot share. If I could figure out how to co-house them with other fast-water species, or even think of such species I might actually want to have at home, then Gastromyzon might be in my future once more.
I didn’t know what it was when I bought it, and I still can’t confirm that this is the beast I brought home that day. It was small and looked somewhat like an oddly-shaped Corydoras or some other kind of tetra and I found it intriguing, if expensive, so I brought it home. I still don’t know what did it in a few days later, but in a way, I’m glad. If it was indeed a Prochilodus, I would not have had the space to house it within a few months.
The plan: Never buy something without actually knowing what it is again, now that I’m an adult and I don’t have to feel like this one pet store trip is the only one I get for the next month or two. Also, I expect to stay away from Prochilodus and other fish of comparable size and activity levels, unless I eventually take up truly monstrous freshwater systems.
Pantodon bucholzi is probably my favorite freshwater fish of all time. Oddly shaped, dinosaur-like, and cryptically beautiful from the sides (where their tails and pelvic rays show best) as well as from above (where they look like reptilian butterflies with transparent windows in their wide pectoral fins), they are striking additions to any fish collection. Additionally, their behavior is an unusual experience. Pantodon is a surface-dwelling fish that rarely goes below the first few centimeters of water and likes to hide beneath floating plants. This creature is such a favorite that, if I ever get a tattoo, it will probably resemble this animal.
Pantodon is a challenging fish that beginning aquarists need to avoid. The butterflyfish is a predator that rarely arrives in pet stores acclimated to prepared foods, and expects to be fed with insects and small fish that visit its surface home. They do not pursue food that sinks away from the surface, so their predatory tendencies are often not an issue for their tankmates, but they do mean that many butterflyfish in captivity slowly starve. My first two Pantodons took to flake food immediately, which was an unusual stroke of luck. As mentioned in Skepticism in the Aquarium Store, the butterflyfish is also a jittery beast, apt to leap from the surface over disturbances as trivial as its tank lights being turned on, so it is important that it have surface cover to hide under and make it feel more secure, and that the lid to its tank be close-fitting and free of gaps. The tank my first few butterflyfish inhabited had little surface cover and a large gap in the lid for the external filter, and these two circumstances combined to make sure that my butterflyfish landed on the floor on three distinct occasions. On one, I noticed quickly enough to return it to the tank; on the other two, what I found was desiccated corpses. I have not bought new Pantodons since, as I currently lack the resources to easily feed fish live foods and my tank currently has just the sorts of small fish that a predatory tankmate might sample.
The plan: If my central-African-themed tank ever takes off (see “bushfish,” above), Pantodon will definitely be part of it, and I will figure out how to feed mine what they will eat. The other fish I already have in mind for that theme prefer ample cover, so making sure the plants reach the surface (or including floating plants as well) will not be a problem. How to get a properly-fitting hood when hang-on-the-back filters are a nigh-universal standard in North America is rather less clear. For Pantodon, though, I will learn.
Spotted Doras / Rafael Catfish
This creature, Agamyxis pectinifrons, is a portly, spiny catfish from South America that is sold under several trade names. It is kin to the “talking catfish” Platydoras armatulus and sometimes sold as the “spotted” version thereof. Like many of its kin, it is a hardy and adaptable beast. While I did not have the amount of woodwork in the tank it would have preferred, tank conditions and tankmates were otherwise acceptable and my pair of these rotund and boldly-colored catfish stood to live a long time. Unfortunately, I purchased some tiger barbs that were a little under the weather without knowing it and introduced an ich outbreak into their tank. As it happens, catfish and other scaleless fish are much more sensitive than their armored fellows to fish antimicrobials like methylene blue. In haste and incaution, I did not account for that in my treatment regimen, and poisoned these beautiful animals alongside the contagion.
The plan: Agamyxis and other doradid catfish are virtually problem-free additions to the kinds of South-American-themed setups I seem to make by accident anyway. I expect no real difficulties, other than finding the fish themselves, in adding them to a tank also containing Corydoras, freshwater angelfish, and similar South American beauties.
The part that makes me particularly sad about the Bunocephalus coracoideus I’ve mistreated over the years is that the first one wasn’t even mine.
When we first moved into my family’s current house in Miami, one of the quirky things we did was get me, my sister, and my brother all started with ten-gallon aquaria. I don’t know that my siblings were a tenth as interested in fishkeeping as I was, but they had a certain baseline enthusiasm and my parents liked the idea of all three of us getting matching tanks. We started with all the same fish, except that my sister got an albino Corydoras (just one, sigh) where the other two of us got plecos. My brother’s and my sister’s tanks were eventually dismantled and the survivors passed on to me after what I assume was lack of maintenance, but I’m not talking about that right now, or even about the gruesome spectacle my brother and I shared of finding our plecos scavenging on the remains of our tiny angelfish who both died of unknown causes.
One fish all three of us bought for our tanks was the banjo catfish, probably Bunocephalus coracoideus. This catfish is, even more than most catfish, inactive. Where most catfish are nocturnal and notorious for not doing much outside of feeding time among owners who observe theirs during the day, banjo catfish spend even nighttime mostly hiding among leaf litter pretending to be sticks. Their efforts at this ruse go so far as to refusing to move when poked, jostled, or lifted with nets. My sister got the prettiest of the three catfish, and somehow, on the second or third day after buying it, I got it in my head that hers had died. Its behavior during repeated poking and liftings seemed to corroborate that conclusion, so I removed it from the tank and put it in a plastic bag in the refrigerator so that it could be returned later in the week.
There was blood in the bag the next morning.
I don’t actually know what that means, but knowing more about the behavior of this species after observing the MUCH-longer-lived pair that remained in the other two tanks, I don’t think my sister’s banjo catfish was actually dead when I put it in the fridge, meaning it asphyxiated and froze to death during the night. I’ve never stopped feeling bad about that, even if she’s almost certainly forgotten the incident. That fish deserved better, and so did she.
The plan: Not doing that. My next banjo catfish will have the woodwork, leaf litter, and lack of disturbances that it deserves and won’t be mistaken for a corpse while behaving naturally. It will fit in nicely with the other South American catfish on my list of redemptions I have not yet earned.
I’ve had two species of danios as pets: the giant danio Devario aequipinnatus and the zebrafish Danio rerio. Both are active schooling species that don’t necessarily take up a lot of “fish-inches” but still require enough space to swim energetically and which are not at their best in small numbers. I’m not convinced the ones I’ve owned had quite enough space, but that was not the error that has added these two species to my mental registry of wrongs to right. My giant danios met their doom when I was performing a water change and absent-mindedly forgot to dechlorinate the new water. By the time I realized what happened, the danios were not the only blanched, irrecoverable victims. As they had lived fairly comfortably in my setup before that, this error was particularly tragic.
My zebrafish met a still less pleasant fate. I kept a school of them in a tank with the African cichlids that gave me the story about fish territoriality in Skepticism in the Aquarium Store 2. Those cichlids made a point to eat everything below a certain size in that tank, which meant all of the zebrafish…but one. On several occasions thereafter, I tried to get more zebrafish to keep that one from being distressed by its solitude, and the cichlids proceeded to eat all of the new ones over the next few days and leave only the slightly larger, older zebrafish. It died on its own before I could separate the cichlids from everything else, and I did not get more zebrafish.
The plan: Most of the other fish I’d like to keep prefer calmer, more sedate tankmates than Devario and Danio species would be, so I’m not sure how to best address the needs of my hypothetical future giant and zebra danios. Loaches and red-tailed sharks are probably a good start, as well as a tire track eel from above.
Dwarf Underwater Frog
The dwarf underwater frog, Hymenochirus curtipes, is not a fish. Sold under several names, it is subject to many misconceptions, several of which I’ve fallen for over my years of fishkeeping. I’ve managed to avoid accidentally getting the young of the much larger and more predatory beast Xenopus laevis instead of actual dwarf frogs by recognizing the dwarf’s distinctive rough skin and lateral eyes, so they didn’t grow up and eat all of their tankmates. Instead, my dwarf frogs all lived in tanks that were too tall for them. Somewhat weak swimmers, H. curtipes cannot endure the additional effort of swimming a long distance to get air and eventually exhaust themselves if forced to, even if dense plants provide off-the-ground rest points. These frogs are also unenthusiastic feeders and often lose out against more eager seekers of sinking food, such as many of the tankmates I picked for mine, adding starvation to the mix of problems they often experience in captive situations. Against this backdrop, the one that snuck into a hole in my filter intake pipe and drowned when it couldn’t escape seems like a mercy.
The plan: Though native to the same areas as the butterflyfish and bushfish above, those predators would not let dwarf underwater frogs last for very long in a shared system, so these frogs won’t be adding to the central-Africa theme. Instead, if I revisit them, they will have a tank set up for their specific needs, heavily planted but with a low water level. This setup will probably not be suited to other inhabitants, except possibly other mostly-aquatic frogs like the smaller Bombina species.
Several species of fiddler crabs, genus Uca, are sold in pet stores’ fish sections. These unfortunate creatures are usually doomed, and mine were no exception. Fiddler crabs live on shorelines, in tide pools, and in estuaries, and tolerate highly variable salinities as a result. They can live in freshwater environments for surprisingly long periods, but not as long as they live in the brackish waters they prefer. They are also not fully aquatic, and need to exit the water periodically to breathe and live out their terrestrial behaviors. When housed in ordinary aquaria, they have a habit of climbing filter intake pipes and other protrusions, falling out of their tanks, and dying of desiccation elsewhere in their owners’ homes…which is how most of mine met their dooms.
The Plan: There are several semi-aquatic and terrestrial crabs I’d like to keep someday, and most of them need similar conditions: brackish water and a haul-out area. If I’m careful, I might even be able to build their home into the brackish tank concept I mentioned for freshwater soles.
It’s both humbling and heartening to revisit my past mistakes. Knowing that even the most accomplished aquarist (I title I cannot begin to claim) has, on their resume, a variety of failed attempts and rookie mistakes can be encouraging for a new practitioner, liable to otherwise imposter-syndrome themselves out of a hobby. This is also a reminder of how far I have come…and how far I have yet to go.
Here’s hoping I get to build all these exhibits someday, and surround myself with the riotous diversity and color I have long desired. Maybe I’ll even try marine fish someday, and make a whole new crop of mistakes.