Overnight the jerks in the jerk tank left nothing but bones of the behri. Final size seems around 10" at 3.5 yo. As stated, the fish grew ok the first year, year and a half - 2.5" in 4 months, then 4" in the following year, then 1" in the next two years.
This means it was feeding ok at the beginning but something kept shifting in its feeding habits and it fed less and less over time, while wasting away and not growing much.
Based on our experience, it seems that some mouth-sucking grazing cyprinids, such as Black shark aka Labeo chrysophekadion, also Labeo congoro are able to learn to take dry feeds like pellets and occasionally thawed fish and attain adult ages and sizes in our hobby rather easily, while others, such as behri, and Cirrhinus microlepis as another example, are unable and perhaps require to be kept in conditions where algae and plankton are plentiful.
From literature:
"Occurs in upland reaches of the Mekong. Inhabits rocky stretches of the main stem of Mekong during the dry season and moves into tributary streams during high waters. Found in riffle and slow deep reaches. Herbivorous, feeding on algae, phytoplankton and periphyton. Not known to persist in impoundments. At Stung Treng below the Khone Falls, the species migrates upstream at the start of the rainy season in May-June and downstream in the dry season from November to February. At Sambor and Kratie as well as just south of Khone Falls, it moves downstream at the onset of the rainy season and upstream in the dry season. The reason for such movement seems to be the presence of the important tributary system, Sekong-Sesan-Srepok rivers. Fishermen reported that this fish migrates from this system into the Mekong during receding water and migrates upstream the tributaries during the rainy season, possibly to spawn. Upstream the Khone Falls, this fish begins migrating upstream in the dry season (February-May) and continues into the beginning of the rainy season. This movement may, in fact, be two separate migrations: a dry season non-reproductive migration of smaller fish and an early rainy season migration of larger fish in spawning condition. Undertakes upstream migrations from Khone Falls all the way to Chiang Khong in northern Thailand which are triggered by the increase of water levels and the change in water-color from clear to red-brown. Migrates upstream in schools together with other cyprinids such as Labeo cf. pierrei, Cirrhinus microlepis, Labeo chrysophekadion and Cyclocheilichthys enoplos as well as the loach, Botia modesta. Marketed fresh."
https://www.seriouslyfish.com/species/incisilabeo-behri/ "A specialized grazer of algae and associated organisms which it rasps from the surface of rocks and other solid objects using its specialised mouthparts."
https://www.mekongfishnetwork.org/bump-headed-fish-incisilabeo-behri/ "In the Mekong basin, an unusual bump-headed fish called Incisilabeo behri (also known as Bangana behri) migrates out of the Sesan, Srepok and Srepok (the 3S) rivers as juveniles into the mainstream Mekong. They may head downstream to the border of Kratie and Stung Treng Province, or upstream to southern Laos PDR and northeastern Thailand for feeding purposes (grazing on algae on rocks). The species spawns in the middle of the Sekong River in July and August. The maximum size recorded is 60 cm. Wonders of the Mekong project staff came across this colorful specimen for sale at a market in Stung Treng, Cambodia.
In Attapeu and Sekong Provinces in southern Laos, villagers have created protected areas to that have helped conserve this species in the dry season, and have also made attempts to ban fishing during its spawning season. Incisilabeo behri is listed in the IUCN Red List as “Vulnerable” (Red List in 2011), and major threats include being targeted with gillnets during the spawning season and feeding migrations. The increasing use of electrofishing gear and dams proposed on the Mekong and 3S rivers could have a major negative effect on the species during its migration. More research and conservation planning is needed to understand and protect this unique Mekong fish species!"
