Keeping the Real-Life Species from Finding Dory
Author: Jeremy Gosnell
Not only did Pixar’s film Finding Nemo raise the profile of marine life in mainstream culture worldwide, it also introduced many children to the exciting hobby of keeping fish. The story of a clownfish that ventures on an oceanic quest to find his son received universal praise and led to an explosion of interest in marine aquariums, especially those housing the film’s three main characters: Marlin and Nemo (two percula clownfish), and Dory (a Pacific blue tang).
Magic in the Aquarium Hobby
Aquarium outlets around the country reported increased sales in tanks designed to keep clownfish, along with a surge in sales of the species featured in the film. As parents met their children’s demands for everything needed to begin their new hobby, they were soon surprised to learn how different keeping a marine fish tank was from a freshwater one. Unlike bettas or goldfish that can thrive even in the absence of regular oversight and maintenance, marine fish need sizable aquariums, exact water chemistry, a varied diet, and a host of complex elements just to remain alive in captivity. Some parents learned the ropes and began enjoying the pastime, while others abandoned the idea altogether.
Enter Finding Dory, the long-awaited sequel to Finding Nemo. The new film takes place six months after the events of the original, when memory-challenged Dory suddenly recalls her childhood and sets out on a quest to find her parents. Like the first film, it’s predicted that Finding Dory will spur popular interest in marine aquariums. Considering that the hobby has seen a host of technical innovations and a considerable investment in captive-raised fish species in the 13 years between films, it’s possible that this new group of novices may fare better at maintaining a marine tank than the budding aquarists that were inspired by the first film.
To help guide Finding Dory fans (and their parents) in keeping fish from the film, this article profiles some of the species featured in it and suggests which ones are excellent choices for youngsters just starting out in the hobby. If you decide to satisfy your child’s desire for a Nemo or Dory of his or her own, following these recommendations can save you some money, time, and tears.
Dory: Pacific Blue Tang (Paracanthurus hepatus)
The Pacific blue tang (Paracanthurus hepatus) has been a mainstay in the aquarium hobby for years. Like Dory, real Pacific blue tangs have bright blue coloration with a dark black stripe that forms a unique pattern over the body and a bright yellow caudal fin outlined with black on the top and bottom. Of all the fish species featured in the film, this one isn’t the most difficult to keep, but its sensitive nature means that first-time fishkeepers will have a lot to learn before being able to successfully care for it in the long term.
To start with, all tangs require good water quality with high oxygenation, low nutrients, and low nitrate levels. In addition, there must be no phosphate present in the water. Pacific blue tangs do best when there is adequate water flow, which requires several circulation pumps in the tank to recreate the gentle currents found on a coral reef. Pacific blue tangs need multiple hiding spots and can become overly stressed if placed in an aquarium without them.
Due to their high-quality water requirements, tangs should be placed either in a full reef aquarium capable of housing sensitive living corals or a fish-only aquarium with live rock (FOWLR). Live rock is home to a host of marine microbes and other beneficial life that act as additional filtration and aids in improving water quality. Successfully keeping them also requires investing in a good protein skimmer, which uses oxygen and water to remove organic waste from the tank.
Diet plays an important role in the long-term health of Pacific blue tangs (or any tang, for that matter). In the wild, this fish is primarily herbivorous, so its captive diet must be supplemented with freeze-dried seaweed or green vegetables, such as broccoli. This can easily be provided by purchasing a marine fish seaweed mixture and clipping it in the tank via an algae clip. Pacific blue tangs also need a mix of other foods, such as mysis shrimp, finfish, squid, and mussels, and greatly benefit from having their food supplemented with amino acids and vitamins.
Nemo and Marlin: Percula Clownfish (Amphiprion percula)
The recent surge in the number of clownfish breeders means that many of the specimens purchased today have been born and raised in captivity. As a result, they are far easier to keep than wild-caught clownfish. This is due to the fact that captive-bred clownfish carry less disease and readily accept prepared aquarium foods.
Percula clownfish (Amphiprion percula) are generally considered a beginner marine fish. One individual or a pair does well, even in an aquarium as small as 30 gallons (114 liters). If keeping an individual, it’s possible to do so in one of the popular nano-reef tanks that are commercially available. These tanks have filtration, lighting, and sometimes heating already included, providing an easy to maintain, all-in-one marine system.
Clownfish need to be provided good-quality marine water but tolerate higher nutrient levels better than species like the Pacific blue tang. Percula clownfish can tolerate some nitrate in the water, but if it exceeds 25 ppm, it’s possible that they will succumb to stress.
Clownfish do well on a diet of pellets supplemented with flakes, frozen foods, and other prepared marine foods. They generally accept food quickly and often remain healthy in captivity.
No Anemones for Nemo
Clownfish are famous for making their home within the stinging tentacles of sea anemones. Be advised that it’s far easier to keep Nemo than it is to keep his anemone home. Anemones require pristine water quality, circulation, and exact water chemistry in a home aquarium, which necessitates the constant management of a host of parameters. In addition, most anemone species also need expensive high- output lighting specially designed for reef tanks. If you’re new to keeping marine fish, a captive-raised percula clownfish is a good place to start, but don’t attempt anemone keeping until you’re more knowledgeable in the hobby and have accumulated some hands-on experience.
Jacques: Skunk Cleaner Shrimp (Lysmata amboinensis)
Similar to how the character Jaques in Finding Nemo quickly cleaned Nemo when he first arrived in the aquarium, skunk cleaner shrimp (Lysmata amboinensis) clean dead skin and external parasites from marine fish. They also perform this role in the aquarium and will often set up a cleaning station where fish can come and receive service. It’s this reason, along with their bright red and yellow coloration, that they are popular in the marine aquarium hobby.
Like all invertebrates, these shrimp require good water quality, with phosphate levels kept at 0 ppm and nitrate kept below 10 ppm. In addition, they require balanced water chemistry that has the proper concentration of calcium, degrees of carbonate hardness (dKH), and magnesium. This aids them in maintaining a healthy shell and also encourages molting on a regular basis.
Cleaner shrimp thrive in both nano and large marine tanks. They do best in either a reef aquarium or a FOWLR tank. Luckily, skunk cleaners don’t get all their food from fish skin and external parasites; they also scavenge nearly all types of food in an aquarium. With a little extra care and some attention to detail, they make the perfect tankmates for a percula clownfish and aid in consuming uneaten food before it pollutes the water. Watching them clean a fish is an entertaining and educational experience for both children and adults. As far as invertebrates go, they aren’t that difficult to keep healthy.
Seahorses (Hippocampus spp.)
As with clownfish, seahorse keeping has benefited greatly from the introduction of captive-raised livestock that were bred, born, and raised in an aquarium. Years ago, it was extremely difficult to get wild-caught specimens to feed in captivity, making them almost impossible to keep. Captive-raised seahorses, however, readily accept food and tend to thrive in aquariums. It’s possible for a beginner aquarist to keep them, as long as it’s understood that they cannot be housed in community tanks because they often cannot compete with most other aquatic species for food.
Anchoring—a process in which they wrap their tail around an object and literally remain attached there—is vital to their health, and objects on which seahorses can anchor in the aquarium is a necessity. They are not aggressive or fast swimmers, so they commonly remain anchored throughout the day, occasionally venturing off to feed or to move around. Artificial corals, plants, and other soft-surface decorations that are long and slender work well as anchor posts.
While they are delicate swimmers, their aquarium requires a good degree of water circulation to ease their ability to move around and ensure any uneaten food makes its way out of the water and into filtration. If kept in a non-reef tank, they prefer subdued lighting because bright reef lighting sometimes causes them stress.
Seahorses generally consume only one food in captivity: frozen mysis shrimp. It’s important to fortify this fare with vitamins and amino acids, as it’s often the only food that seahorses will consume.
With some research and dedication, it’s possible for a beginning aquarist to keep a seahorse tank, and a 30-gallon (113-liter) aquarium is enough for one or two pairs. I don’t recommend a nano-reef or an all-in-one tank for them, simply because they don’t need high-output lighting and prefer a long tank as opposed to a cube. A good beginner species to keep an eye out for is Hippocampus erectus; they rank as one of the easiest-to-care-for species.
Gill: Moorish Idol (Zanclus cornutus)
Moorish idols (Zanclus cornutus) are the epitome of aquatic grace, featuring long streaming fins and a well-blended yellow, black, and white coloration. However, they are a species not even recommended for advanced aquarists. Over the years, many experienced hobbyists have tried keeping them only to encounter complete failure.
It’s believed that idols feed on sponges in their natural habitat, and even prepared marine foods that feature sponges are lacking in a necessary nutrient obtained only in the wild. This leads to slow starvation and an overall degradation of health. They are also susceptible to poor water quality and a host of diseases within the aquarium. Even in cases where it appears all of an idol’s needs have been met, there’s just a 50-50 chance it will survive. This is one species that I recommend everyone—from novice to expert—leave on the coral reef.
Yellow Longnose Butterflyfish (Forcipiger flavissimus)
The yellow longnose butterflyfish (Forcipiger flavissimus), along with other fish in the family Chaetodontidae, is an interesting animal that has a unique set of keeping requirements. Like tangs, they aren’t the best beginner marine fish, largely because of their sensitive nature.
All butterflyfish species require an aquarium of at least 55 gallons (208 liters) or more. Also, it’s imperative that the tank is stocked with cycled live rock, which is submerged oceanic rock (often deceased corals) that is home to a host of organisms. They use their long snout to grab tiny animals from rock crevices. Often, newly acclimated specimens will not accept prepared food.
A yellow longnose butterflyfish is not compatible with a newly set up aquarium, and any butterflyfish requires a well-established tank that is free of boisterous tankmates. Luckily, these fish adjust to captive life far better than other family Chaetodontidae species. Once acclimated, they will accept prepared foods such as a frozen mixture of squid, clams, and mussels. A varied diet is important because they need some algae in their diet but are unlikely to take it from an algae clip. This means feeding a food mixture that contains algae in small bits that they can grab with their tiny jaws.
Butterflyfish are susceptible to some diseases, including marine ich, but most often they succumb to stress, either from living in a tank that’s too small or when suffering constant harassment from a tankmate. Like other marine fish, they require good water quality with no phosphate, low nitrate levels, and the right balance of salinity and pH. While I don’t recommend yellow longnose butterflyfish for a novice aquarist’s first foray into marine fishkeeping, experienced aquarists will find it a striking addition to an established marine tank.
Four Stripe Damselfish (Dascyllus melanurus)
Damselfish, in general, are the hallmark beginner’s fish. They are hardy, tolerate a wide range of water conditions, and accept nearly any prepared food. Many aquarists got their start in fishkeeping by housing a group of damselfish.
Four stripe damselfish (Dascyllus melanurus) are bright white and black as juveniles, but as they grow, their bright black and white coloration dulls and they suddenly become aggressive. Often, they will eat small shrimp and invertebrates in the aquarium and pick on their tankmates. Although damselfish (including the four stripe) are resilient, many fishkeepers have stopped keeping this species due to its abrupt change in behavior, size, and coloration as it matures.
Silver Moonies (Monodactylus argenteus)
The silver moony (Monodactylus argenteus) is a perciform fish found in the Red Sea whose range extends southeast to New Caledonia and Australia. It is one of the most commonly kept fish in brackish water aquaria and can tolerate both brackish environments and full oceanic salinity. Silver moonies are often acclimated to brackish water before purchase, which means a marine aquarist must slowly acclimate them to full salinity (1.026 specific gravity, or sg). This is done by starting with brackish water (1.005 sg) and then raising the salinity over the course of several months, usually by 2 to 4 points a month, until reaching full salinity.
Silver moonies are known to be hardy and grow up to 12 inches (30 cm) in the wild, commonly reaching 8 inches (20 cm) in the aquarium. In captivity, they are known to enjoy a host of foods, including frozen marine fish blends, broccoli, freeze-dried seaweed, and especially live blackworms.
They are often kept with archer fish and halfbeaks, as these species also inhabit brackish water. Any relatively docile marine tankmate would do well housed with them. Several individuals can be kept together in a very large aquarium (200 gallons [757 liters] or more) to replicate a school in the wild. Although schooling behavior can be tricky to reproduce in captivity, an aquarist can often find a small group of fish for sale that is already schooling. In this case, it’s likely the behavior will transfer to their new aquarium.
While moonies are hardy, I’m not sure that they can be recommended as beginner marine fish. A lot of care has to be taken to acclimate them to marine water, which may necessitate the setup and maintenance of a separate tank to allow for the arduous process. Even if the silver moony catches your eye when you’re new to the hobby, get some experience under your belt before attempting to keep one. However, if you have a large tank and can find individuals already acclimated to saltwater, they make a striking addition to any tank.
Finding a Conclusion
With a colorful cast of characters and a heartwarming story, Finding Dory is sure to delight children and adults alike. If, after watching the film, you or your children can’t resist the urge to bring some of its characters’ real-life counterparts into your home, remember that patience, research, and good water-quality management practices are the key to caring for and keeping your newly found favorite species.