Just to let you guys know, I bought the 400g 104.76 Tunze "coral gum" and just mixed some up to stick an Acro frag down. Don't waste your money on this stuff. You can get a large 2lb (1lb A, 1lb B) "trial" sized container of the same purple silicone putty from Smooth-On for about $10 less than the .8lb Tunze kit. They mix the same, look the same and adhere similary to porous surfaces. They are both a standard non-toxic silicone rubber mix and you can even use it to make candy molds and ortho molds from it. The Equinox 35 is their "fast" setting mix with a 1-minute pot-life and (for practical purses, cure time) of 7 minutes. The 38 is a little slower with a pot-life of 4 minutes and a "cure" time of 30 minutes. The 40 is too slow for reef use IMO and has a tendency to migrate a lot before it sets up. If you're keen on making fake corals, fake nems, fake live rock or acrylic rock supports you should check out their aquarium decor section with how-to vids.
http://www.smooth-on.com/Silicone-Rubber-an/c2_1115_1133/index.html?catdepth=1
http://www.smooth-on.com/Silicone-Rubber-an/c2_1115_1133/index.html?catdepth=1

