Mushroom frag

[I was thinking about fragging my red and blue mushroom but they will be hard to take off from the rock. Can I just cut them in half in the tank or will the toxins be bad for the tank? If I need to take them off the rock how would I do that?]
 
[If the tank is 29g or larger, I think you could cut one or two without doing damage.]
 
[It's a 55 gal that's been up for about 2 yrs now. the only corals i have in there are mushrooms, GSP, xenia, and a torch coral. still looking to add more corals. Thanks alot Mark]
 
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