Honestly the khuli loaches are always out if you have 6 or more. Zooming everywhere
I've had a group for 7 years now. They inhabited various tanks. The first one was driftwood and leaf litter dedicated to them only. They hid in the leaf litter most of the time but were seen dancing early morning...
The 2nd tank was a heavily planted tank. In this tank they were out all the time in bright lights. It was the most suitable I think as they felt secure among the plants.
Their current tank is my pond and they are rarely seen there again, hiding in the clay pebbles in the plant baskets or underneath caves, even underneath the clown loach pvc pipe. But they bred in this tank and not long ago I saw a baby kuhli. It probably made it hiding in the clay pebbles...