Red Broadtail Goldfish (Carassius auratus l.f.) 9-10 cm

Overview

The Red Broadtail Goldfish (Carassius auratus l.f.) is a classic fancy goldfish variety prized for its rich red colour, rounded body and elegant, broad caudal fin. At 9-10 cm, this fish is a great size for aquarists looking for a healthy young specimen with plenty of potential to develop into a stunning display fish as it matures. Broadtail goldfish are known for their graceful swimming style and eye-catching finnage, making them a favourite for well-planned coldwater and temperate aquariums.

As with all fancy goldfish, this variety is best kept in a spacious, well-filtered aquarium with excellent water quality and plenty of room to swim. They are hardy and rewarding fish, but they do require more care than many beginners expect due to their size, waste output and need for stable conditions. When properly housed, they can live for many years and become a true centrepiece in the home aquarium.

At Tropical Fish Co, we select healthy live fish and pack them with care for fast UK delivery. Every order is covered by our live arrival guarantee, giving you confidence when buying online.

Care at a Glance

Origin & Natural Habitat

Goldfish are domesticated descendants of the Prussian carp, originally developed in China over many centuries through selective breeding. The Red Broadtail is a fancy variety created for its colour, body shape and flowing fins rather than for natural survival in the wild. Unlike wild carp, fancy goldfish are not suited to ponds or aquariums with strong currents, overcrowding or poor water quality.

In the wild, the ancestors of goldfish inhabited slow-moving rivers, lakes, ponds and marshy waters with soft substrate and abundant plant life. This background explains why goldfish prefer stable, oxygen-rich water and plenty of space. Their natural biology also means they are opportunistic feeders with a broad diet, and they can be enthusiastic eaters if given the chance.

Tank Setup & Water Parameters

For the best results, house your Red Broadtail Goldfish in a large aquarium with powerful filtration and regular maintenance. Goldfish produce a significant amount of waste, so filtration should be sized generously and water changes should be routine. A bare-bottom setup can make cleaning easier, though smooth sand or rounded gravel may also be used if kept clean.

Decor should be simple and safe. Avoid sharp ornaments, narrow gaps and abrasive surfaces that could damage the fins. Broadtail goldfish are not fast swimmers, so they do best in a calm environment with open swimming space. Live plants can be used, but choose hardy species such as Anubias, Java fern and some Cryptocoryne, as goldfish may nibble softer plants.

Recommended water conditions are 18-22°C, with a pH between 6.5 and 8.0. Stability is more important than chasing exact numbers, and sudden swings should be avoided. Good dissolved oxygen levels are important, especially in warmer rooms, so surface agitation and efficient filtration are beneficial. If you are keeping more than one goldfish, increase tank volume accordingly to maintain water quality and reduce stress.

Acclimation should be slow and careful. Fancy goldfish can be sensitive to abrupt changes in temperature and water chemistry, so allow the fish to adjust gradually on arrival. This helps reduce stress and supports a smooth transition into its new home.

Feeding Guide

Red Broadtail Goldfish are omnivores and thrive on a varied diet. A high-quality sinking or slow-sinking goldfish pellet should form the staple of the diet, as floating foods can encourage gulping air and may contribute to buoyancy issues in some fancy varieties. Feed small portions once or twice daily, only offering what the fish can consume in a couple of minutes.

To support health and colour, supplement the staple diet with blanched vegetables such as peas, spinach, courgette and lettuce, along with occasional frozen or live foods like daphnia, bloodworm and brine shrimp. A varied diet helps maintain good digestion, vibrant colouration and overall condition. Overfeeding is one of the most common mistakes with goldfish, so it is better to feed modestly and consistently than to offer too much at once.

Because goldfish are active foragers, they will often appear hungry even when they are not. Resist the temptation to overfeed, and remove any uneaten food to protect water quality.

Tank Mates / Compatibility

Red Broadtail Goldfish are peaceful and best kept with other cool-water fish that share their temperament and environmental needs. Suitable companions include other fancy goldfish varieties of similar size and swimming ability. In some larger, well-maintained aquariums, robust cool-water species may also be considered, but compatibility should always be assessed carefully.

Avoid housing broadtail goldfish with fast, nippy or aggressive fish, as their flowing fins can be damaged and they may struggle to compete for food. Tropical fish that require warm water are also unsuitable, as are very small species that could be outcompeted or accidentally eaten. Tank mates should be chosen with care to ensure all inhabitants can thrive in the same conditions.

As a general rule, broadtail goldfish do best in species-only setups or with other fancy goldfish of similar body shape and swimming speed. This reduces stress and makes feeding and maintenance much easier.

Why Buy from Tropical Fish Co

When you order live fish from Tropical Fish Co, you can expect healthy stock, careful packing and dependable service from a specialist UK aquatic retailer. We understand how important it is to receive fish in excellent condition, which is why we offer a live arrival guarantee and fast UK delivery on eligible orders.

Our team is committed to supplying quality livestock and clear care guidance so you can set up your aquarium with confidence. Whether you are adding a single feature fish or building a carefully planned goldfish display, the Red Broadtail Goldfish is a timeless choice that combines beauty, personality and long-term appeal. With the right setup, this elegant fancy goldfish can become one of the most rewarding fish in your collection.