Maas' Spiketail Loach

Vaillantella maassi is one of the most distinctive hillstream loaches in the hobby, immediately recognisable by the elongated filament extending from the tip of its caudal fin — a feature unique among hillstream families. Its slender, elongated body is patterned with fine reticulations and occasional spots on a warm tan-brown background, and the species can reach up to 12 cm making it one of the larger hillstream loaches available. It is native to the hill streams of Borneo and Sumatra.

In the aquarium, V. maassi is somewhat less extreme in its flow requirements than Gastromyzontidae species, tolerating moderate rather than very strong current. This makes it somewhat more accommodating of standard aquarium equipment, though strong oxygenation must still be maintained. It is an omnivore and feeds more actively on prepared and frozen foods than purely herbivorous hillstream species.

The spiketail loach is a peaceful species and can be kept in groups. Its elongated body and characteristic tail filament create a striking visual effect in motion, particularly in a well-planted hillstream aquarium where its graceful swimming style can be fully appreciated. It is best housed with species of comparable size — smaller tankmates may be intimidated by its larger body.

Water: 22–26°C, pH 6.0–7.0, GH 3–12, KH 1–6; moderate to strong flow; well-oxygenated water; less extreme in flow requirements than Gastromyzontidae species. Tank: 100 L minimum; elongated tank preferred to accommodate swimming; smooth substrate with boulders and driftwood for shelter. Feeding: Omnivore — sinking pellets, algae wafers, frozen bloodworm, daphnia, and brine shrimp; varied diet promotes best colouration. Breeding: Rarely bred in captivity; no reliable records; condition with modest cooling and increased flow. Compatibility: Peaceful; suitable for larger hillstream biotopes; avoid very small tankmates that may be displaced at feeding time.