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The Complete Aquarism Glossary

Decode the jargon. Everything you need to know about fish keeping, from "Ammonia Spikes" to "Zebra Danios".

All Terms
Anatomy
Aquarium Problems Equipment & Hardware Filtration & Water Flow Physiology Tank Setup Water Parameters

A

Air Breathing Fish
Anatomy
Air breathing fish are species capable of absorbing oxygen directly from the air in addition to using gills.
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F

Fish Gills
Anatomy
Fish gills are respiratory organs that extract oxygen from water and remove carbon dioxide from the bloodstream.
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G

Gill Filaments
Anatomy
Gill filaments are thin, feathery structures within the gills that allow oxygen exchange between water and blood.
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L

Labyrinth Organ
Anatomy
The labyrinth organ is a specialized respiratory organ that allows certain fish to breathe atmospheric oxygen directly from the air.
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Lateral Line
Anatomy
The lateral line is a sensory system that allows fish to detect vibrations, water movement, and pressure changes around them.
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O

Operculum
Anatomy
The operculum is a bony flap that covers and protects a fish’s gills while helping regulate water flow for breathing.
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S

Swim Bladder
Anatomy
The swim bladder is an internal gas-filled organ that helps fish control buoyancy and maintain stability in the water column.
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