X-ray tetra

Behaviour and habits

The X-ray tetra is a small, almost transparent shoaler whose see-through flanks reveal its bones, with bright yellow, black-tipped fins adding a splash of colour. It is extremely tolerant and peaceful, schooling loosely in mid-water and rarely causing any trouble. It adapts to a wider range of water than almost any other tetra, which makes it one of the best first fish for a beginner, though it still prefers to be in a group of six or more.

What to feed, and how often

It takes micro-pellets, crushed flake and small frozen foods at any level, and is never fussy. Feed one or two light meals a day, only what it clears quickly, and vary the diet for colour and condition. Its small size and calm nature mean it is easily fed alongside other peaceful community fish.

Water changes and maintenance

Change about 25% weekly, matched closely to the tank. It is the most forgiving tetra for water chemistry and tolerates a range of conditions, but like all fish it does best with clean, stable water and no sudden swings.

Care and how easy it is

One of the best beginner tetras — hardy, peaceful and adaptable. Keep a group of six or more in a planted community, and it will settle quickly and show its subtle, glassy colours.

Lifespan

With good conditions and steady water quality, this species typically lives around 3–5 years in a home aquarium; some individuals live longer.

Common health problems

It is rarely ill, even in less-than-perfect water, which is one of the reasons it suits beginners.

If it gets sick

Keep the water clean and treat the rare infection promptly; its toughness means problems are usually the result of long-term neglect rather than a delicate constitution.