Huge potential problem here. Just resealed a tank using GE Silicone II (black), having read that I'd be ok as long as the cartridge says 100% silicone. (which it does). No listings of any biocides, mildewcides etc. on the cartridge. Was speaking to someone this morning who told me that they DO contain such mildewcides, but they're just NOT printing it on the label. I called GE sealant telephone number and lady I spoke to said that indeed it DOES have the mildewcide in it, but the marketing department doesn't advertise it as such. I'm ready to stock my tank and now in fear I'm gonna kill 'em all before I even get started. Any advice?