I need to lay some conjecture to rest (which may only be done by going ahead with my plan and relaying the experience) about GE silicone. I was at lowes searching for sealant to reseal my 29g. I found the GE Silicone section and started browsing. Well at this time all I had read about sealants indicated only that I need look for 100% silicone. I found two choices GE silicone I, and II. Well by looking at the adhesion chart for both it showed that II on a 1-10 scale rated 10 for glass adhesion and I rated a 7. Given the information I had I ass-u-me 'd it would be better. I proceeded to reseal the seams on my tank. Well after noticing the label which read 100% silicone had also a tag for bio-seal (mysterious mildew inhibitor) I began to wonder. 100% silicone plus X% mystery substance =??. Needless to say I've read through many, many forums on the subject and I can't find concrete evidence that I shouldn't proceed with filling and stocking the tank. On one hand there is conjecture because in some years past GE used arsenic (allegedly) in this type of silicone (or that its another mildewcide) It will leach and kill the fish, on the other hand I've also found many accounts of people using it with no ill effects. GE silicone I is recommended by many because its supposedly the same sealant repackaged that AGA sells and uses on their tanks, so in turn thats what everyone recommends. Well those who point against GE II provide some conjecture on the substances that might harm fish in it but no experience/official company word/scientific proof/reasoning for this. There are those using it with success, this whole leaching business sounds a little who-ee to me. So I'm sure some of you out there may or have run into this, I think it'll be fine, we'll sure know after my tank is running. Your comments are appreciated.