The old rule still applies that the larger the aquarium, the better its resistance and biological stability. However, practice shows that a marine aquarium does not have to be large at all. Proper filtration technology, lighting, circulation and a suitable stocking density are sufficient to set up a biologically stable nano aquarium of 30 to 60 liters (16 to 26 US gal.). In these conditions we can successfully create a mini coral reef with beautiful corals and marine animals. Here is a suggestion of fish that can form a suitable stock for our dream nano reef.
A perch-shaped fish from the humphead family that can be found in the wild in the Indo-Pacific waters, Indian Ocean or Gulf of California. It inhabits lagoons and coral reefs at depths from 1 to 12 meters, forming numerous shoals. It feels best among hard corals, mainly of the genus Acropora. It reaches size up to 8 cm. It is a long-lived fish and in proper conditions it can survive even 15 years!
Green humpback whale is probably the most popular fish in marine aquariums. It owes its popularity to beautiful, subtle coloration. Its scales are highly iridescent and – depending on lighting – shimmer from green to light blue.
Despite the fact that this fish belongs to humpback whales family (which are mostly quite aggressive) it has relatively calm character and is quite peaceful towards the rest of tank’s inhabitants. Food sources for this species include artemia, zooplankton, nematodes and daphnia, which should be enriched with frozen and dry food.
Pseudochromis fridmani is a fish from Diademidae family. It lives in sea water up to 60 m deep. It seeks hiding places between rocks, near coral reefs. It is an endemic species to the Red Sea. It reaches the size of up to 7 cm. Its common name is dottyback orchid.
Pseudochromis fridmani is very popular and easy in breeding. It can be not only an addition to reef aquarium but thanks to its beautiful colors and interesting personality it also makes the whole composition more attractive. However, it is worth to make sure that the aquarium has plenty of hiding places among the rocks.
Although this species of fish is peaceful (it moves mostly between its hiding places), but from time to time it may “prophylactically” frighten other, especially smaller fish. Pseudochromis can be fed with frozen food – artemia, mosquito larvae, nematodes as well as dry food.
This is one of the most interesting saltwater fish from the apogon family. It is probably an endemic species and is found only in the archipelago of Indonesian Banggai Islands. It lives in shallow waters up to two meters deep and hides in sandy-muddy bottom covered with sea grasses. It grows up to 8 cm long.
Pterapogon kauderni has a very characteristic appearance (the body of the fish is flattened, the tail is strongly indented, dorsal and anal fins are elongated) and coloration (it has light spots and dark stripes), that is why it is sometimes called “sailfish”. It is also an interesting fish in terms of behavior. It moves slowly and majestically and in case of danger it can hide between long urchin spines. Like cichlids it keeps fertilized eggs in its mouth and after hatching the young – in case of danger – run away to their parents.
Cardinal Apogon is quite hardy and easily adapts to new conditions, therefore it is recommended to beginner aquarists. It should be fed with frozen food (artemia, mosquito larvae, daphnia) and small dry food.
This goby-like fish lives in the western Pacific Ocean – from the south coast of Japan through Indonesia to Australia. It is found near coral reefs, in sandy lagoons and calm bays at depths of 1 to 25 meters, where it hides in rock crevices among sedentary invertebrates and in shrimp burrows. In the wild, it usually remains in symbiosis with shrimps of the genus Alpheus.
Cryptocentrus cinctus grows to a size of about 8-9 cm. Like all gobies it has two dorsal fins. The body of this fish is crowned with a large head, large eyes and a wide mouth. The predominant variety is lemon yellow with numerous light blue dots.
This species requires an aquarium with hiding places and plenty of sand. The behavior of cryptocentrus in breeding conditions does not differ much from the one in the wild – first it digs a burrow in the substrate under a piece of rock, from where it peeks out only the top of its head with eyes scanning the surroundings in search of something suitable to consume. It should be fed with frozen plankton, chironomid larvae, anemone and dry food. Cryptocentrus also cleans the bottom from food remains. As far as temperament is concerned this fish is not aggressive towards other creatures, although it is territorial.
The stocking proposed in this article gives a chance that in our marine aquarium each of the described fish will find its proper place and there will be a harmonious coexistence, which will positively affect their health and condition.
Featured photo: Wikipedia