siamese flying fox - Badman's Tropical Fish

The fun thing is that my article even contains a photo where you can see both fishes as they sold me both species as mentioned. Look at the second photo and on the fish at top. This is a Flying Fox while all the others are siamese algae eaters on the photo.
You can see it as the Flying Fox has a white body under the black line while a Siamese Algae Eater has it golden like above the black line.

Flying fox may be a common name that is applied to siamensis as well as other fish.

It is not so much a problem telling them apart from the Garra, Flying Fox, Chinese Algae eater etc. The real problem is telling the 5 different Crossocheilus themselves apart...seeing there are only 2 of them that are true algae eaters (Siamensis and Langei) the other 3 will not eat much algae and prefer fish food. These fish are all caught in the same place so in a tank it can be near impossible to get the 'right' one. Seeing the Siamensis are caught in a different area and very rarely imported your only hope is at finding a Langei.

Siamese flying fox fish in fish tank aquarium

Lots of shops mislabel these fish so Siamese algae eaters can also often be found under Flying Fox as well as other names. Another species sometimes confused with the Siamese algae-eater and the flying fox is the stone-lapping fish (Garra cambodgiensis). It looks a bit like a faded flying fox, with a heavier body and less color in the fins. The stripe does not run through the tail. This fish will graze on soft slime algae.

Siamese Flying Fox and Goldfish combo

This fish resembles a Siamese algae-eater but with more color. It’s actually attractive enough to be kept for its looks alone. The flying fox (Epalzeorhynchos kalopterus) eats a bit of algae and is related to red-tailed and rainbow sharks. Like the sharks, it’s quite territorial toward its own and similar-looking species, so keep no more than one per community. Adult size is up to 6 inches. This fish and its shark relatives will all graze on soft slime algae.

Siamese algae eater - Wikipedia