I have kept Kuhli Loaches as pets in the past, and in this article I’ll share some of the knowledge and experience I’ve gained about these fascinating fish.
Hailing from places like Indonesia, Malaysia and Java, the Kuhli Loach is often found in slow-moving streams with lots of leaf litter and sandy bottoms.
Usually shy and prone to hiding, this loach species becomes more confident when you build a home for them that mimics their natural habitat.
Keeping Kuhli Loaches as Pets
Growing to 3–4 inches long, this species doesn’t produce a heavy bio-load.
They are eel-shaped, with yellow and brown banding and a white underside. They can also be solid-colored — some are pinkish white and others are brown. Their downturned mouths are decorated with 3 sets of barbels.
And with the right care, the average lifespan of the Kuhli Loach can be more than 10 years.
These fish are natural bottom feeders and will search out any leftovers from other fish. While they spend a lot of time hiding, they are eager to come out during feeding. My own Kuhli Loaches would at least stick their heads out of hiding spots to reach morsels of food nearby.
If provided enough hiding places within the aquarium, this species will feel much more at ease. Add live plants, like Java ferns and Cryptocorynes, to give more coverage. Those plants are slow-growing but will do just fine for the loaches.
Bright lighting is not really essential, since the plants mentioned don’t need a lot and the loaches actually like it a bit darker.
Kuhli Loach Behavior
Kuhli Loaches often like to squeeze themselves into tight spaces to hide.
But they aren’t always loners — they’re also quite social and do best in groups of 4–6, and a group of a dozen will do very well if enough space is available.
When they are observed in groups, it’s not difficult to see why they do so well together. They are never far apart, no matter what they’re doing, and they follow each other to sources of food.
I’ve caught them darting between low-growing plants in the sand and sometimes hanging off of taller plants, as if they were part of some playground.
- The loaches are mostly nocturnal with their scavenging activities. However, they do come out at dusk and dawn as well.
- With time, they may also become bolder during daylight hours. My own group of 4 always managed to sneak out just before the lights came on in the morning.
Housing for Kuhli Loaches
Make sure to cycle the tank before putting any fish in it.
Kuhli Loaches are sensitive to rapidly changing water chemistry, so it’s best to have it stabilized beforehand.
Other notes on housing:
- Make sure your aquarium is no smaller than a 20-gallon tank to accommodate these active fish. They prefer water to be soft or medium-hard and with a pH of 6–7. The best water temperature range for Kuhlis is 75–85 F.
- Kuhli Loaches are from slow-moving waters in their native regions, so try to simulate the same in the home aquarium: Turn down the flow on the filter, and place a sponge guard on the intake pipe to prevent any fish injuries.
- Kuhlis may jump out of aquariums if there is an opening. Prevent this with a tight-fitting lid.
- Kuhli Loaches have thin skin that can be scratched and injured, so use fine sand or smooth gravel as a substrate in their tank.
- Place driftwood, smooth stones and even PVC tubing into the tank to create hiding places. Tannins that leach from the driftwood may actually help replicate the loach’s natural habitat and water chemistry.
- If you’re housing Kuhli Loaches as pets with any other fish, make sure they aren’t big enough to eat them. Smaller schooling fish like danios, minnows and tetras are good choices. Err on the side of caution with more aggressive fish species.
Diet — What Do Kuhli Loaches Eat?
Besides eating the leftovers from other tank mates, Kuhli Loaches will eagerly take sinking pellets made for bottom dwellers.
They relish live food, like bloodworms and brine shrimp.
Use 1–2 good sinking pellets as the staple diet and offering live foods occasionally. These loaches love meaty foods and sometimes will take vegetable matter.
Blanche a bit of zucchini or squash so it sinks to the bottom, and the creatures should zero in on the food just fine.
Interested in keeping Kuhli Loaches as pets? Check out these fascinating bottom feeders:
Breeding Kuhli Loaches
The strange thing about these fish is that they can be a challenge to breed, and sometimes it ends up happening by accident.
As long as your group is large enough, they might actually sort things out themselves. My own group never bred, but probably because the group comprised only 4 members.
Large water changes, usually 50–75%, seem to trigger breeding behavior.
Sometime after this change, female loaches begin to develop eggs and swell to twice the size of males. Male and female pairs start to erratically swim up and down the sides of the tank. They will intertwine their bodies and swim across the water’s surface several times, eventually releasing bright-green eggs.
The eggs will float for a while and then sink down to the bottom. The eggs have a slightly adhesive quality at this stage and will attach to plants and other objects when they sink.
For the best chance of the eggs surviving, the adults will need to be moved to another tank. In the breeding tank, the eggs can develop until they hatch into fry.
Additional advice on caring for these very young Kuhli Loaches:
- Don’t completely clean the tank — some of the leftover mulm is beneficial for the first couple of days of the fry. The mulm actually contains tons of protozoa that the fry can feed on in their first stage of life. The aquatic plants also have micro-fauna living on them that will serve as another source of food.
- After 4–5 days, offer some commercially made fry foods, sinking foods and micro-worms. After about another week, give the fry some fresh-hatched brine shrimp.
- To maintain water quality, do small daily water changes to keep the fry healthy. After about 6 weeks, the fry will be about 1 inch long, and some may need to be moved to another tank — the fry can number in the hundreds.
Once the young Kuhli Loaches reach 2 inches in size, you can sell them to other fish keepers. Local fish clubs and fish stores may take some of the loaches, too.