Aquarium glossary

African cichlids

Spectacularly coloured freshwater fish native to large African ponds. They require hard, alkaline water, the opposite of Amazonian fish.

Allelopathy (chemical warfare between corals)

The release of toxic substances by corals and invertebrates to compete with their neighbors. An often underestimated factor in reef design.

Alternanthera reineckii

Aquatic plant with an intense red colour. One of the most accessible colourful plants in planted freshwater aquariums.

Angelfish (Pterophyllum)

South American cichlid with an elegant and majestic shape. The king of the tropical community aquarium.

Anubias

Slow-growing African aquatic plants with leathery leaves. Indestructible, suitable for any aquarium. They bind to rocks and wood, never buried.

Aquatic mosses

Rootless plants that attach to rocks and wood. Easy to grow, decorative and perfect shelter for fry and shrimp.

Aquatic plants

Plant organisms that live completely or partially submerged. They absorb nitrates and phosphates, produce oxygen and provide shelter for fish.

Aragonite

Crystalline form of calcium carbonate. It makes up the skeleton of corals, living sand and the substrate of calcium reactors.

Archerfish (Toxotes)

Brackish fish that spews jets of water to knock down insects from branches above the surface. One of the most fascinating behaviours of the aquatic world.

Arowana

Primitive fish with an elongated and majestic body. The 'freshwater dragon'. Some Asian species are worth thousands of euros.

Artemia (brine shrimp)

Small saltwater crustaceans used as live food. Newly hatched nauplii are ideal food for fry and small fish.

Axolotl

Mexican aquatic amphibian that remains in larval form throughout its life. It's not a fish but lives in an aquarium. It needs cold water.

Betta (fighting fish)

Freshwater fish with spectacular fins and a territorial character. Males cannot coexist with each other. Easy to raise but often poorly maintained.

Biofilm

Thin film of bacteria and microorganisms that covers all submerged surfaces. Natural food for shrimp, snails and fry.

Bioload (biological load)

The total amount of organic waste produced by living organisms in an aquarium. Excessive bioload overloads the filter and leads to the accumulation of toxic substances.

Blennidae (Blenniidae)

Bottom fish with a friendly and curious behaviour. They perch on rocks and observe the environment. Many species are herbivorous and reef safe.

Brackish aquarium

Intermediate environment between freshwater and marine with variable salinity. It is home to fascinating species such as archerfish, pufferfish and mudskippers.

Bucephalandra

Rare aquatic plants from Borneo with colourful, iridescent leaves. They bind to rocks and wood like Anubias.

Butterflyfish (Chaetodontidae)

Marine fish with bright colours and an elongated snout. Most are not reef safe because they feed on coral polyps.

Cardinal fish (Apogonidae)

Peaceful and easy to breed marine fish. Oral incubators: The male holds the eggs in his mouth until they hatch.

Caridina and Neocaridina shrimps

Two kinds of beloved freshwater dwarf shrimp. The Neocaridina are easy, the Caridina more demanding but spectacular.

Clean-up fish and invertebrates

Organisms that help keep the aquarium clean by eating algae, debris and food scraps. A complement to maintenance, not a replacement.

Clownfish (Amphiprion)

Among the most iconic and resistant marine fish. They live in symbiosis with anemones but in the aquarium they also adapt without them. Ideal for those starting with the reef.

Compatibility between fish

Not all fish can live together. Choosing aquarium companions requires consideration of temperament, size, parameters and diet.

Coralline algae

Pink-purple calcareous algae that encrust rocks and glass in marine aquariums. Sign of good health of the aquarium and natural competitors of unwanted algae.

Corydoras

Small armored catfish from South America. Peaceful, social and tireless land scavengers.

Crabs in the reef

Some crabs are useful scavengers in the reef. Others are predators that attack corals and fish at night. The choice must be made with caution.

Cryptocoryne

Genus of aquatic plants from Southeast Asia. Easy, elegant and suitable for aquariums with moderate light.

CUC (Clean Up Crew)

The set of scavenger invertebrates that keep a marine aquarium clean: snails, hermit crabs, crabs, starfish, urchins, shrimps.

Cycling (nitrogen cycle)

Cycling is the process by which the colony of nitrifying bacteria is established in a new aquarium. Without complete cycling the fish die.

Denitrification

The biological process that converts nitrates into nitrogen gas. It occurs in anaerobic conditions (without oxygen) within live rock, deep substrates and special filters.

Diatoms

Brown unicellular algae that appear in new aquariums. They form a brown film on glass, substrate and decorations. They disappear on their own as they mature.

Discus (Symphysodon)

Considered the kings of the tropical freshwater aquarium. Majestic fish that require warm, soft and very clean water. Not for beginners.

Echinodorus (Amazonian sword)

Large and majestic aquatic plants of South America. Ideal as a focal point in the aquarium. Easy to grow.

Ember Tetra (Hyphessobrycon amandae)

Bright orange micro fish ideal for planted nano aquariums. Only 2 cm in length but intense colours in pack.

Floating plants

Plants that float on the surface of the water with hanging roots. They absorb nitrates quickly, create shade and provide shelter for fish.

Freshwater puffer fish

Curious and intelligent but aggressive fish. They have a continuously growing beak and must be eaten with hard food (snails).

Gambusia (anti-mosquito fish)

Small freshwater fish used to control mosquito larvae. Rustic and prolific, it also lives in stagnant waters.

Gobies (Gobiidae)

Small bottom fish perfect for the reef. Some species sift through the sand, others live in symbiosis with pistol shrimp.

Goldfish (Carassius auratus)

The oldest ornamental fish in the world. Much more demanding than you might think: they require space, filtration and cold water.

Guppy

Small, easy and colourful freshwater fish. Ideal for beginners. It reproduces extremely easily.

Hillstream Loach

Stream fish with a flat and aerodynamic body. They stick to rocks and glass in cold water and strong currents.

Killifish

Small freshwater fish with extraordinary colours. Many species lay eggs that survive dried in the mud for months.

Koi carp

Ornamental pond fish originating from Japan. They can live for decades, reach considerable sizes and develop extraordinary colours.

Lionfish (Pterois)

Predatory marine fish with poisonous spines. Beautiful but not reef safe: eats shrimp, crabs and small fish.

Live rock

Limestone rocks colonised by bacteria, sponges, microorganisms and small invertebrates. In marine aquariums they are the main substrate for biological filtration.

LPS corals (Large Polyp Stony)

Hard corals with large polyps. More resistant than SPS, with showy tentacles and intense colours. Also suitable for those starting out in the marine world.

Ludwigia

Genus of stem plants with shades ranging from green to blood red. Among the most colourful in planted freshwater aquariums.

Malawi cichlid aquarium

A biotope dedicated to the cichlids of Lake Malawi. It requires hard, alkaline water, lots of rocks and attention to shoal dynamics.

Management of starfish in the aquarium

Starfish are fascinating but challenging. Serpentine stars are the most suitable for the reef.

Mandarin fish (Synchiropus splendidus)

One of the most beautiful and colourful marine fish. Difficult to feed: eats only live copepods. Requires mature aquariums with abundant microfauna.

Mangroves in aquarium

Mangrove seedlings grown in the sump or aquarium with submerged roots and emerged leaves. They absorb nitrates and add a unique natural element.

Marine invertebrates

The set of corals, anemones, shrimps, crabs, snails, stars and urchins that populate a reef aquarium. Often more demanding than fish.

Mediterranean aquarium

Cold sea water aquarium that replicates the Mediterranean ecosystem. A fascinating alternative to the tropical reef with local fauna.

Neons and cardinals

Small tropical fish with a characteristic blue and red colour. Among the most popular freshwater fish. They should be kept in packs of at least 10 specimens.

Nitrification

The bacterial process that converts toxic ammonia to nitrites and then to nitrates. It is the crucial half of the nitrogen cycle in any aquarium.

Nitrifying bacteria

The microorganisms responsible for the nitrogen cycle. They convert toxic ammonia into nitrites and then into less dangerous nitrates.

Nitrogen cycle

The biological process that transforms toxic fish waste into less dangerous substances. Without a mature nitrogen cycle no aquarium can function.

Ocellaris clownfish

The most widespread clownfish in aquariums, made famous by the film Nemo. Easy, resistant and available in many captive bred varieties.

Ornamental shrimp

Freshwater and marine crustaceans farmed for their bright colours. Neocaridina and Caridina are among the most popular inhabitants of nano aquariums.

Oscar (Astronotus ocellatus)

Large, intelligent South American cichlid. Recognizes the owner and interacts with him. Requires huge aquariums.

Phytoplankton

Unicellular microalgae cultivated as food for filter-feeding corals, bivalves, zooplankton and invertebrate larvae.

Piranha

South American predatory fish famous for their sharp teeth. In the aquarium they are often shy and fearful. They require large aquariums.

Plecostomus (cleaner fish)

Sucking catfish of the Loricariidae family. The most popular algae eaters in freshwater aquariums. Pay attention to the adult size.

Pogostemon

Genus of aquatic plants native to Asia. Among the most versatile for aquascaping with unique textures and shapes.

Rasbora

Small peaceful fish from Southeast Asia. Ideal for planted aquariums and nano aquariums. They should be kept in packs.

Red aquatic plants

Red plants are the greatest challenge in planted freshwater aquariums. They require bright light, iron, CO2 and often low nitrates.

Reef safe

Indicates that a product, a fish or an invertebrate is compatible with a reef aquarium without damaging corals, anemones and other invertebrates.

Refugium macroalgae

Marine algae grown in the refugium to absorb nitrates and phosphates naturally. A biological alternative to chemical filters.

Reproduction of fish in the aquarium

Breeding fish in captivity is one of the most rewarding challenges. Each species has specific requirements for spawning and fry rearing.

Rotala

Genus of stem plants with colours ranging from green to deep red. The most demanding species are among the most beautiful of planted freshwater.

Rotifers

Microscopic planktonic animals used as first food for fish larvae and marine invertebrates. Essential for marine breeding.

Scavenger fish: myths and reality

The concept of cleaner fish is a dangerous myth. No fish keeps an aquarium clean on its own. They have their own needs.

Sea anemones

Stinging invertebrates that host clownfish in symbiosis. Beautiful but demanding: they require intense light, perfect water and a mature aquarium.

Sea urchins

Voracious herbivores that control algae in the reef. Useful but can damage corals with thorns and move fragments.

Snails in the aquarium

Gastropods useful as scavengers and algae eaters. Some species are introduced voluntarily, others arrive as stowaways on the plants.

Soft corals

Corals without rigid calcareous skeleton. They are the easiest to maintain in marine aquariums, with bright colours and rapid growth.

SPS (Small Polyp Stony) corals

Hard corals with small polyps. They are the builders of coral reefs and represent the greatest challenge in marine aquariums.

Starfish in the aquarium

Fascinating invertebrates but often difficult to keep in captivity. Serpentine stars are the most suitable for the reef.

Tang (surgeon fish)

Herbivorous marine fish with a compressed body and bright colours. Essential for algae control in the reef but require large aquariums.

Tanganyika cichlid aquarium

A biotope for the cichlids of the deepest lake in Africa. Unique species with complex social behaviours.

Tannins (amber water)

Organic compounds released by wood and leaves that colour the water yellow-brown. They create the blackwater effect loved by many tropical fish.

Tunicates (sea squirts)

Brightly coloured filter-feeding marine invertebrates. They are often found on live rock. Some are beautiful, others haunting.

Uric acid and dissolved organic compounds

Waste products of fish metabolism that accumulate in water. Not measurable with standard tests, they are removed by water changes.

Vallisneria

Fast growing aquatic ribbon plant. Creates a rolling prairie effect. Suitable for beginners, does not require CO2.

Wild bettas (wild-type)

Wild Betta species. Biotope fish with fascinating natural behaviours, different from the farmed Betta Splendens.

Wrasse (Labridae)

Colourful and active marine fish. Many species are reef safe and useful for controlling parasites and weeds.

Zooxanthellae

Symbiotic microalgae that live in coral tissues. They provide energy through photosynthesis in exchange for protection and nutrients.