Matt Clarke manages to track down one of the rarest loaches in the hobby, the Forktailed loach, Vaillantella maassi, at a wholesaler in Northumberland.
Common name: Forktailed loach
Scientific name:Vaillantella maassi
Origin: Malaysia, Borneo and Brunei on the north coast.
Size: Around 12cm/5"
Diet: Not known. Probably insect larvae, crustaceans and detritus. Try offering bloodworms, artemia and astaxanthin-rich dried foods to enhance the orange dorsal colours.
Water: Neutral or slightly acidic is probably preferable. These ones were doing fine in hard water.
Aquarium: I'd guess that these things are found in quite fast-flowing water, so a decent flow rate would be good. Like Khuli loaches, these are fairly secretive and tend to hide among the decor most of the time. To make them feel at home, place plenty of smooth pebbles and stones in the tank so they can hide easily. Avoid nippy fish which may attack the large, soft dorsal fin and the long tail.
Notes: This is probably the rarest and most sought after species of loach there is. These fish don't look that colourful at the moment, but they can turn chocolate-brown and develop a bright orange stripe which runs along the entire dorsal surface. Adults are stunning! A few have turned up in bycatch with other loaches before (especially Kuhlis), but we're not aware of a whole batch of these turning up in one go. They're one of many rare species which appear on import lists, but never arrive up when ordered. The global demand is probably high, while the supply is limited. They're fast movers and we can't imagine that they'd be easy to catch in the wild, which may explain the price.
Similar species: There are two other Vaillantella in the genus, V. cinnamomea and V. euepiptera. Check out the brilliant loaches.com and FishBase for more details on these ones.
Availability: These fish, which are probably the only ones in the UK at the moment, were imported by Tom Halvorsen Ltd (0797 7098127; www.tomhalvorsen.co.uk).
Price: This is the ultimate fish for loach fans, so expect to pay up to about 40!