Of course it will ruin my water when its rotten but I will def. remove them long before they ruin my water and Acorus can normally survive for 12 months totally submerged and only then will begin to die if not exposed to air for some time. I will be moving in about 6months and if I remove them when I'm moving and keep them out for a couple of weeks them I have a 12 more months of them in my tank.lol, im working on an LFS, so not all LFS are like that.
the plant you have now is not an aquatic plant, but you can try it if you want but like fresh newby told you it will ruin you water once its rotten.