Boy, you guys sure know how to get yourselves in trouble by giving incomplete descriptions or explanations!
Green sheetrock has a mold inhibitor. It is intended for use in kitchens and bathrooms where there is expected to be high humidity levels on a regular basis. It does not "off-gas" this inhibitor, to answer halmus' question. Many kinds of paint will off-gas volatile organic compounds (VOCs) or worse. So do many glues and adhesives. The best paint for easy maintenance, enamel, is also the worst for giving off fumes and other nasties for several weeks after application.
That's why it is so important NOT to start finishing the house after you set up your aquarium. This stuff should all have been finished and given a chance to cure and the air in the house to have changed several times before introducing your tank. Is there a guarantee that these modern chemicals will kill your aquarium? No, of course not. They are just another POSSIBLE threat to your tank's health - and yours.
Dave.M