coolie loaches caught out of the rocks: how big and do they breed in aquaria?

[bettaMagenta]

I picked up these little guys when they were still pretty small, just 3 or 4 of them. They're in a tank with big pebbles, and for a while, I hardly ever saw them. Lately, though, they've been popping out a lot more often. It's like they're having trouble squeezing between the rocks - sometimes they need to make a U-turn and try again. Maybe now that they're bigger, they're more interested in coming out during feeding time instead of waiting for food to drift down.

So, I'm wondering, is this as big as they get? And do they ever breed in tanks like they do in the wild? They seem like pretty solitary animals, even though they're supposed to do well in groups. When I do see multiple ones at the same time, they're usually on opposite sides of the tank.

[fishing]

Kuhli loaches aren't typically schooling fish, they might occasionally shoal a bit, but it's not common. Getting a small group is more about making them feel secure and encouraging them to come out. Your loaches do appear to be full-grown, around 3-4 inches. As for breeding, it's extremely challenging and would require a lot of effort - the success rate is very low, so it's not something I'd recommend trying unless you're experienced. If you were to attempt breeding, kuhli loaches prefer a sand substrate, as they like to dig. Those large stones in your tank can be difficult for them to navigate and may even cause harm. If changing the substrate isn't feasible, they'll likely adapt, but sand would be a better option for them.

[happyone]

Kuhli loaches do need a sand substrate, I completely agree with fishing on this. They're a species that likes to dig and often spend time buried, so a soft sandy base is essential. Using coarser gravel can cause them stress or even injury, and it can also affect their feeding behavior. I've read that Pangio semicincta, or the Kuhli Loach, really benefits from this type of setup.

[bettaMagenta]

They're polished pebbles, no sharp edges, I thought they'd stay hidden in the Java ferns, but they've always managed to squeeze into the gaps. Even now, they still love swimming in the spaces between the pebbles... every so often, they'll get stuck and back up, sometimes even surfacing before diving down into another gap. They still spend most of their time cruising the gaps, just like they would in fine sand. I'm sure they've been eating all the food that's fallen into the gaps since they were tiny, but now that they're bigger, they've started coming out to compete with the corys at feeding time, finding food on the surface of the rocks. Still, most of the time, they're out of sight, cruising the gaps.