They also come in a variety of colors, such as pink, orange, albino and gray, and can vary in colour from yellow to olive green, to a common light brown or grey with lighter undersides.
Pond loaches are bottom-dwelling omnivores, feeding mainly on algae or scavenging organic materials, and may also eat on tubifex worms and other small aquatic invertebrates.
Pond loaches are very hardy fish that can live in poor-quality water, and can survive short periods of drought by producing a layer of moisture-trapping mucus to keep themselves damp.
[6] Unlike most other fishes, the pond loach can burrow into and hide in soft substrates, breathe atmospheric air through enteral respiration if necessary, and survive for long periods of time outside of the water.
[4][7] For the pond loach to survive on land for extended periods of time, it has physiological adaptations to reduce toxic ammonia concentrations in the body and maintain homeostasis and normal functioning of tissues.
For this reason, many aquarists and keepers will adjust their fishes' communal feeding time to be in the evening, an important point to consider if cohabitating pond loaches with other species.
Not being a tropical species by nature, water temperatures above 70 °F to 75 °F (21.11 °C to 23.89 °C) are not recommended for, and can cause respiratory issues, fatigue, and even death, in pond loaches.
They show virtually no aggression or hostility to any other tankmates, including their own kind, mostly minding their own business despite being a highly sociable species; if housing multiple individuals, which is usually recommended, pond loaches will often "cuddle" and rest huddled-together.
Given their somewhat "goofy" and cantankerous nature, they are not particularly aloof or shy, and thus can develop a "friendliness" towards their caretakers, swimming around their owner's hands and arms, allowing for physical contact and even hand-feeding.
If a pond loach successfully jumps from the water (and is not subsequently caught by a bird or other animal), it may crawl on the ground for some time, breathing atmospheric oxygen, before eventually suffocating.
Despite their ability to move terrestrially between shallow bodies of water in the wild, something many species do (like killifish), they do not have the same respiratory adaptations as, for example, the lungfishes or mudskippers.
Botias possess notably different, downward-pointing snouts with visibly fewer barbels, as they are more active hunters of prey than the bottom-dwelling pond loaches.
The pond loaches prefer a water pH of 6.5–8.0, but, as a temperate-climate freshwater species, will tolerate far more acidic conditions, even for extended amounts of time, with little negative reactions.
Although these two species have numerous differentiating traits, individual kuhli and pond loaches may resemble each other while young and at the usual age and size of what most fish stores market.