|MadSci Network: Microbiology|
Sorry this repsonse is too late to help you. I missed it the first time it was sent to me. I hope this is still somewhat helpful.
First of all, your slime would need to be inoculated with a mold that can grow in that system. The system contains some antimicrobials in the glue as well as the borax. If a type of mold that grows under these conditions lands on the slime, it will need time and temperature conditions to grow. If you are leaving it at room temperature, then that should speed things up a bit. Most molds will show signs of growth in 5 to 7 days at room temperature if growing on a medium that supports this growth. The mold will also require oxygen, which means there will need to be some air exchange. This may result in drying of your slime, which may decrease the amount of water available for the mold and further slow growth.
Now, for the color. This will depend on if the dye is absorbed by the fungal mycelia. Even if absorded, the dye may be chemically altered and no longer be the same color.
I would love to hear how your experiment turned out. I wish you well in your future science experiments.
Try the links in the MadSci Library for more information on Microbiology.