Macrognatus shows its tail from out the gravel

Two fish hide in a hole. A macrognatus and a loach. They don't hide entirely. Both tails are outside.
Two tails

Tail of a macrognatus

Macrognatrus is digging in gravel, where it searches for worms or merely hides from me when I clean the tank.

If you put some shells and stones on the gravel macrognatuses and loaches like rambling in holes between the shells.