Gobie and Shrimp Pair Question

[RCFA]

Mine seem to show up in a new hole every night around feeding time. Always out front. It is great to see the shrimp making the hole and I do have to target feed a bit as nothing really settles near them if I don't put the food right out in front of their hole. every day their old hole is closed up and they are back out the next night somewhere else. They must have a huge network of tunnels under my rock.