"Rescape" with a pistol shrimp?

[TinCanHero]

Hello!

My tank is just over a year old, this is my second tank and second time having a PS. ive had a pistol shrimp with a helfrichi for around a year, although i haven't seen the helfrichi in a few months (this has happened once before and then he popped out one feeding time - I don't think they are pared, he just uses his burrows to live in). In this time he has made many burrows under the main scape and outcrop with many entrance's around the tank. and stolen any frag I put on the sandbed.

My tank is a RSR200xl and has a single rock a made up from smaller bits and has "feet" with a larger top. along with a single rock fist size off to the side on the sandbed.
The pistol over time has undermined the large rock (I guess is wasnt on the glass completely, i did prop it up with rubble in places also) and it now tilts at a weird angle. hes also filled in under the rock so the sand in places is now covering the bottom of the rock that should be floating. one of the frags propping up one of his tunnels has a aptasia on it so id like to remove that also.

Id like to lift the main rock and readjust it along with removing the excess sand under it to reset the scape but I'm pretty scared of collapsing his burrows and potentially trapping him and killing him as my sand is quite fine. Usually I don't mind what he gets up to since he is so fun to watch when he is working by the entrance but the main rock is unstable and it needs moving as its shifted quite a bit recently.

any advice on going about this?

kind regards,
Tincanhero.

 

[aSaltyKlown]

The best way would be to completely remove the structure. I've rescaped/switched tanks a with few times with a PS. Lift the structure straight up, one time, I did not see it on/in the sand after I removed the rock, it had gone into a crevice within the rock, so be careful when setting the rock down. I did this during a water change, I drained the water into two 27g black storage tubs so I only had a few inches of water left in the tank. This makes it easier to catch livestock. If you were only readjusting, I wouldn't remove the fish, but I would take out the PS. At the very least keep an eye on it, it should move, but why take chances when putting the rock back in.

 

[Cell]

Rock should always go in first against the glass, then sand. You can perform your operation at a time when you have located the current position of the pistol shrimp and can work around it.