no way really, if you acclimate it long enough 99% of the water will be your tank water anyway. According to Bob Fenner it is actually a good idea to add the water to the tank, read what he has to say here on in CMA, p. 391.
"This is one of those rare instances where adding shipping water (as long as it doesn't seem to be outright contaminated) into your system with the new livestock is a good idea. ... There is a large body of evidence showing that echinoderm water has a therapeutic effect on other organisms and the system itself. I can only ask you to trust me; this isn't hocus-pocus."