What Fish Is in Your Tank?

What the aquarium fish identifier reads from a photo

A clear side-on photo shows the traits that separate tank species: body shape, fin type and size, coloration, and patterning like stripes, spots, or iridescence. The tool reads those visible cues and suggests the most likely species, its common name, and the features behind the match, useful for a new arrival or a fish you inherited with a tank.

• Body shape and size relative to the fins.
• Fin clues: long flowing fins, a sail-like dorsal, or barbels around the mouth.
• Color and pattern: vertical bars, horizontal stripes, spots, or a metallic sheen.
• Distinctive features like an armored body, a sucker mouth, or an extended tail.

How to photograph a fish in a tank

Tank photos fight glare, motion, and dirty glass. Turn on the tank light, turn off the camera flash, and wait for the fish to pause broadside to the glass. Shoot straight through a clean panel so reflections do not wash out the colors, and get level with the fish rather than shooting down from above.

• Clean the glass and let the water settle before shooting.
• Use the tank light, not the flash, to keep true colors.
• Wait for a calm, side-on pose with the fins open.
• Crop to the single fish you want identified.

Aquarium fish identification: reading the result and confused species

Many popular aquarium fish come in look-alike groups and color morphs, so treat the result as a ranked shortlist. Tetras, barbs, danios, and rasboras overlap in shape; cichlids and plecos include dozens of similar species; and selective breeding creates color forms that differ from the wild fish. Compare the listed features against your fish before deciding.

• Neon versus cardinal tetra by how far the red stripe runs.
• Common versus bristlenose pleco by size and snout.
• Guppy, molly, platy, and swordtail overlaps among livebearers.
• Farm-bred color morphs that do not match a wild-type chart.

Care notes are a starting point, not a stocking plan

Any adult size, temperament, or care notes in the result are general guidance for the species, not a plan for your specific tank. Water parameters, tank size, current tankmates, and individual behavior all matter. Before you buy, rehome, or mix fish, confirm compatibility and care needs with a trusted aquarium reference, a specialist, or your local fish store.

When to use the app or ask a specialist

When the photo is soft or two suggestions look equally likely, the fastest fix is a sharper side-on shot through clean glass in better light. For a saved log of your tank and multi-angle comparison, continue in the Fish Identifier app. For a tricky ID or a stocking decision, ask an experienced aquarist, a specialist community, or your local fish store.