Jawfish don't actually sift sand looking for food; they're digging their burrows so the only sand they'll work on is where they want to make a home. So if you're looking for something to clean the top surfaces of your sand throughout your tank, a jawfish probably isn't what you want.
They are, however, very fun to watch and can complete small engineering miracles with little shells and pebbles
They aren't extensive
tunnelers like
pistol shrimp, but if they decide to build a burrow under a corner of your rockwork, you may find it undermines it, sometimes at the expense of the jawfish. I lost one to a cave in
Generally speaking, they'll live in one primary burrow and have a secondary one that may be not much more than a bolt hole. Sometimes though, they'll dig several burrows before settling on one or two locations they favor. They do tend to dump sand too, where you might not want them to but not nearly so bad as the sand sifting gobies; those things drive me nuts!
Jawfish can be pretty disruptive to your sandbed, depending on the lay out of your tank, but that can be mitigated somewhat by providing them with shells and pebbles for building in one location. In my nano I had one burrow that was a piece of live rock with a hole in it that I sunk down into the sand and then left plenty of building materials near the entrance. The jawfish took right to it and never caused any more problems with digging. I lost that jawfish to some type of infection but I'd definitely like to have another one someday.
HTH,
Alice
"A BRW Original"
