Gold Chinese algae-eaters (Gyrinocheilus aymonieri), also known as sucking loaches and Indian algae eaters, are commonly sold at about 2 inches long, but they can grow to be fairly large, averaging 7.5 to 11 inches. As these fish grow, they can become semi-aggressive toward slower fish, so the species' best tank mates are fast-moving fish. You can house multiple Chinese algae-eater fish in a single habitat, but it's best to have at least six so that they can create a pecking order.
Male and female Chinese algae eaters can be housed together without breeding, because they don't breed well in basic aquariums. When you purchase them as juveniles, it can be nearly impossible to tell the gender. If you decide to house multiple algae-eaters in your aquarium, you won't know the gender of the fish until they're adults. Sexing is not necessary, but it's possible if you're curious.
Male Vs. Female Algae Eaters
An adult male Chinese algae-eater will develop tubercules or "horns" on the nose. An adult female will have a much thicker and rounder body than a male, whose body is thin and narrow.