Biota Captive Bred Nano Gobies in the Home Aquarium

Biota Captive Bred Nano Gobies in the Home Aquarium

Authors: Felicia McCaulley, Iyoul Aldrin

Many years ago when saltwater aquariums were first popularized, the standard recommendation for the smallest saltwater aquariums for hobbyists was 50 gallons. Nano reef aquariums were considered to be difficult, and pico tanks just weren’t recommended. With advancements in aquarium equipment and our hobby’s collective husbandry knowledge base, nano and pico aquariums are not only possible, but many aquarists now have thriving small aquariums for many years.

The oceans are unfathomably large, and saltwater fish have as much room to spread their fins and swim as they could ever want. That means there aren’t many reef fish that can be kept in a small aquarium. Even the small, popular clownfish do best in tanks that are at least 30 gallons. What fish could possibly comfortably fit inside an aquarium smaller than this? 

Captive bred nano gobies in the genera Trimma, Eviota, Elacatinus and their small close relatives are perfect for smaller aquariums because they remain small all of their lives and are easy to feed. Being demersal (living on the substrate), they don’t need much room to swim around. These fish fit well in nano, pico, and micro tanks. 

Wild nano gobies can be sensitive and difficult to feed. They often don’t have an appetite for the prepared foods we have available to us in the aquarium hobby and prefer to eat live foods. By the time they reach the hobbyist, they’re sometimes already severely underweight and need to learn to recognize prepared foods quickly or they will die. Captive bred gobies are better choices because they’re raised in captivity on the prepared foods readily available to aquarium hobbyists. They also don’t go through a starvation period like wild caught gobies may experience moving through various different holding facilities and systems during transport.

Captive bred gobies spend their entire lives with humans. Once acclimated at home, they will recognize their humans and entertainingly appear during feeding times, darting around to catch food from the surface or water column. 

Very tiny species like Eviota and Trimma prefer more gentle flow and are social fish that will be more active in small groups, but may also be kept singly. They have a similar disposition to neon gobies. Eviota and Elacatinus tend to be more active in the water column than other gobies, hovering out in the open if provided an area with slower water movement. 

These Nano gobies are entirely reef safe. They won't bother coral or sessile invertebrates, and even the tiniest ornamental shrimp are safe with them. 

Biota nano gobies are easy to keep in home aquariums because they are so easy to feed. Biota captive bred nano gobies are raised on small pellet foods like Easy Reefs DKI pellets and Masstick, tiny Reef Nutrition Tdo pellets, and a variety of frozen meaty foods like Hikari Mysis and baby brine shrimp and PE Calanus.

Since captive bred gobies are well conditioned and better suited to life in captivity, they more frequently lay eggs in home aquariums. This gives hobbyists an opportunity to delve into captive breeding themselves. Even if raising the fry isn’t a goal, the courtship, breeding behaviors, and male egg guarding behaviors are exciting and interesting to observe.

Nano gobies for the most part peacefully coexist, and it’s possible to mix different species given enough rock work to establish their own territories. Small quarrels can break out between gobies of the same sex or at feeding times. They may be kept singly in smaller tanks or in small groups in larger tanks. Nano gobies are social fish, so they’ll be more visible and hide less often in small groups of their own species.

Most gobies in the Trimma and Eviota genera are hermaphrodites. Some are sequential hermaphrodites, others are simultaneous hermaphrodites with protogyny (changing from female to male) being the most common form of sequential hermaphroditism in marine fishes. Asterropteryx are born male or female and do not change sex. Males are slightly larger than females on average, though both sexes are similarly sized. 

Spotlights on available Biota captive bred nano goby species

Koumansetta rainfordi - The Court Jester Goby is one of the larger “nano” goby species, growing up to 3” long. These gobies do well singly in a smaller tank of 10 - 20 gallons or in small groups in larger aquariums when added at the same time. Court Jester Gobies also help out with cleaning up pesky hair algae in aquariums, as this is their natural diet in the wild.

Wild caught Court Jesters typically arrive in poor condition, are incredibly finicky eaters, and rarely survive. This is the primary reason Biota decided to breed and offer this species. Because they are raised on prepared foods like small Easyreefs  DKI and Reef Nutrition TDO pellets, Biota turned a difficult fish into a fish that is downright hardy and easy to keep in home aquariums. This is a pretty fish that isn't very shy, and the best part is they will munch on any nuisance hair algae. Biota captive bred Court Jester gobies do well on a diet of small pellets, PE Calanus, Hikari Mysis, and similar omnivore foods.

Court Jester Gobies have a great personality once acclimated, they spend more time swimming in the water rather than hiding like many small gobies. 

Eviota nigriventris - Like other Eviota and Trimma species, this tiny fish works well in nano, pico, and micro tanks. This species is highly variable in coloration in the wild, but the variety Biota Palau cultures has a warm yellow cast to its body. They're often confused with and similar in nature to the closely related E. brahmi. 

Elacatinus oceanops - The Blue Neon Cleaner Goby, is a hardy goby perfect nano, pico, and micro tanks. This species is a facultative cleaner that will gently clean larger fish in your aquarium. They do not rely on cleaning large fish as a food source and will readily accept a wide range of foods like tiny pellet foods, frozen calanus, Hikari baby brine shrimp, and small chopped mysis. They can also live in nano tanks or species only tanks without fish to clean.

Asterropteryx semipunctatus - The starry goby is an adorable stocky reef goby with large, curious eyes that is perfect for nano tanks. They are more boisterous and visible than most other small nano gobies once they settle into a rocky area of the reef tank. Their dark toned bodies are adorned with iridescent light blue spots that are reflective when they catch the light just right.

The starry goby is a very passive reef fish that maxes out at 1.5”. They do well in both nano tanks and larger reef tanks with plenty of rocky hiding places.

Trimma cf. caesiura - The bright red White Spotted Pygmy Goby is an awesome reef inhabitant for those that like different, colorful nano fish. They max out at just over 1” which makes them ideal for nano, pico, and micro tanks, but they're interesting in large tanks, as well. These fish typically hang under shelf rock or in caves and come out frequently to check their surroundings for food.

Eviota brahmi - Brahm's Dwarf Goby has a bright red-orange stripe bordered by white stripes above and below. The fins are transparent, and the dorsal fin is elongated in both sexes. This is a very tiny species, maxing out at 1”. Brahm’s Goby may be more timorous than some other nano gobies when first introduced, but they will reward the viewer with their extremely bright colors and coy behaviors once they are well acclimated. This species will hover in the water column if provided a lower-flow area. 

Eviota storthynx - The Hairfin dwarf goby is a cute nano goby perfect for small aquariums or even micro biotopes. Their coloration is interesting with white blotches and reflective metallic gold flecks on a translucent body and bright red patch on the gills. The dominant male in a group will develop a lighter gray coloration on the head, and the first four dorsal fin rays are elongated. Females have a deeper red patch on the gills and the first two dorsal fin rays are elongated. They can be found guarding nooks and crannies in the rock scape and darting around searching for food. These max out at 1” but are a bit bulkier and more visible in the home aquarium than other tiny Eviota species like the Brahm’s.

This species has a tendency to perch on soft coral in the home aquarium and is particularly fond of Ricordea mushroom and toadstool corals. They can often be seen shimmying through the corals or peaking their heads out of the folds of the corals. 

Eviota lachdeberei - The Cosmic Nano Goby is a fun and beautiful nano goby with a dark body and white dots on the belly and a row of white spots on the dorsal ridge. Two vibrant blood red blotches at the base of the tail stand out with complementing subtle red markings in the eyes and edges on the scales of the ventral side of the fish. This unique coloration makes the goby look like a cosmic scene of black space, white stars, and red nebulae. 

This pygmy goby is perfect for small nano, pico, and micro tanks. They grow to 1” in size but are one of the bulkier and less secretive Eviota species. Mature males can be identified by the first four dorsal spines being elongated.

The Cosmic Goby is interesting in its own right, but if you're a seasoned reefer who is fascinated by symbiotic relationships, the Cosmic Goby is the perfect nano goby for you. In the wild, the Cosmic goby, aka Lachdebere's Pygmy Goby, is typically found associating with Heliofungia plate corals. It would be a fantastic reef display - the Cosmic nano goby in its natural habitat among the tentacles of a long tentacle plate coral.  

Eviota atriventris - The Black Belly Dwarf Goby has very bright red and fluorescent yellow coloration. Their bodies are nearly translucent, and it interestingly appears that the coloration comes from inside the fish. They’re named for the large black spot bisected by a thin white line in the belly area. These can typically be found singly or in groups near shelters of Acropora colonies in the wild. These are one of the more dainty Eviota which max out at just over 1”. They’re a bit more on the shy side, but once acclimated they can often be seen perching on rock or coral or hovering in the water column. Their bright coloration makes them easy to spot!

How does Biota breed gobies? 

In 2021 Biota Palau produced approximately 2,000 captive bred gobies of 8 different species. Biota were the first to breed many of the species we work with such as the Eviota lachdeberei, Eviota brahmi, Asterropteryx semipunctatus, and Eviota storthynx. Some of the fish produced are being held and conditioned as new F1 broodstock for following years. The goby system has a total of 30 tanks and about 3000 liters of water located inside a temperature controlled room. 

Iyoul Aldrin, the Operations Manager at Biota Palau, houses goby broodstock in 30 gallon open circuit tanks with no sand or live rock. PVC tubes are provided for shelter and/or spawning sites. The tanks are maintained with protein skimmers, UV sterilizers, and daily water changes of flow-through ocean water. This keeps the parameters constantly stable and optimal; temperature is 26°C and pH is 8.4. The tanks are siphoned and scrubbed free of algae and detritus at least daily. 

Goby broodstock diets consist of a wide variety of foods including Easy Reefs Masstick, Easy Reefs DKI pellets, Reef Nutrition Tdo pellets, enriched Artemia adult and nauplii, and blended squid and prawn. 

Breeding pairs are chosen by health, size, and coloration. Some species are sexually dimorphic. Those that have phenotypically indistinguishable sexes are observed, and pairs are chosen based on their social interactions. They are conditioned by feeding 3 - 4 times a day with nutrient rich, high protein diets. Once they begin courting/mating, they’re provided with an appropriate spawning site. Some species prefer PVC tubing for spawning, and some prefer flat surfaces; the sides, bottom, and corners of the aquarium glass are popular spawning sites for those that prefer flat surfaces. After spawning, it’s important to increase the frequency of feeding to help them regain energy and nutrients.

The male guards the nest, only briefly  leaving the eggs to eat. During this stage, the safety of the nest takes priority, and the male may lose some interest in feeding. Fertilized eggs are usually yellowish-orange and turn silver just before hatching. Unfertilized eggs will look opaque. Depending on the species the egg size may vary. Egg masses contain about 100 - 200 eggs per spawn.

When the eggs are almost ready to hatch, they take on a silvery sheen, and the eyes of the fry inside are clearly visible. Just before hatching, the eggs are moved to and isolated in a dedicating larval rearing tank. Different species have different hatching days. Mostly smaller fish such as gobies may take 3-5 days while other fish may take 5-6 days.

After hatching, newly hatched goby larvae are fed algae enriched rotifers, copepods, and when they reach a large enough size, newly hatched Artemia. Depending on species, the free-swimming planktonic larvae will go through metamorphosis in about 2 or 3 weeks. During this stage, the larvae “settle” to a benthic lifestyle, also taking on an appearance more like the adult fish. Once larvae settle (“Meta” stage), they are moved to grow-out tanks and fed copepods and Ocean Nutrition sep-art cyst and Micro Artemia cyst enriched with Easy Reefs Easyrich phytoplankton gel. Once large enough, juvenile gobies are trained to eat only pellets ranging in size from 0.5mm - 0.8mm. Like the adults, the goby fry are relatively peaceful and don’t intentionally kill each other, but the smallest may be chased by the dominant fish in the group if enough shelter and territory is not provided.

The Biota Group plans to continue offering these beautiful and interesting nano goby species, and with continued support from aquarists like you, Biota will be able to expand to offer many more species of gobies and other fish in the future!

References

originally published in Reef Hobbyist Magazine May 2022

Thebiotagroup.com

Fishbase.org