How to stop an encrusting coral?
 

I have an encrusting Mystic monti in my tank and I am now at the point where I wish I had never added it. It's not as if it's taken over my tank, but my satisfaction with its good growth has turned to fear over how invasive it has become. Any suggestions on how to slow it down or even maybe kill it?
I think I could fairly easily deeply shade it with new pieces of shelf rock, but a lot of it that wouldn't be easy or feasible. Any suggestions? What have other reefers done? ( I am also over its pink colour!)

Welcome to reefing. I have found that my monti's are not overly aggressive and have always lost out to healthy SPS, Zoas etc. They only go so far. However knowing that they have overgrown other corals the best way to curb their growth is 2 part epoxy, or superglue. I have used it effectively to curb my poccis that are way more aggressive, grow every where and sting everything.

Some have had success with using Kalk paste.

Monti nudis work really well. I have some if you need them.

If I were in your shoes, I'd replace the rock

I've got some dry rock I'd gladly trade you for! 🤣

Removal not feasible
 

Thanks all for the suggestions. Unfortunately rock removal isn't possible, the mystic is running out from a rock central to supporting the main rock tower in my tank. It would really destroy the landscape I love by breaking apart that tower. Figures.
So I think I may try shading some of it which would place it into near darkness, I have chipped some of it away, and I may be able to cover some of it by gluing rubble on top. It might recolonize but it will give me some time. Might also try the glue...

It will grow in the shade. I had a Monti that grew on the underside of a shelf. You could try killing it with another coral.

As Frogger said, Acros dether them from taking over. I have the same problem when my Christmas monti had a growth explosion, however as soon as they touch the Cali Tort and the Purple Bonsai, they got bleached out.

So put an acro frag over them and let the acro encrust and demolish them.

My latest one is my Setting Sun Monti trying to take over but my Purple Bonsai said... Ahh ahhh.

My offer of some healthy fat monti nudibranchs are still out there.

epoxy it up. if you just attach the epoxy in some areas it could be removed later. or my boreman anemone killed mine and they are not that hard to remove after