Any silicone that doesn't have added mold inhibitors is safe with about 72 hours of "curing." The color is not important in this respect. I use GE I, clear because it doesn't seem as stiff as GE II, which is also recommended. Just avoid the silicones meant for bath room caulking. You don't need to pay a lot more for the "aquarium safe" products as long as there is a period of time before you introduce your frogs. There are many other brands that are just as good, perhaps. I just settled on the GE I because for my purposes, it seems to have the most workable consistency and doesn't dry up in the caulk tube between uses. (It just forms a plug you can pull out.) On the other hand, this may not be as strong for supporting heavier pieces of cork bark, etc. This is just an impression I got when I last used it to hold up something that was off balance and it eventually collapsed--but I'm not sure the silicone was to blame rather than my design.
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Patty
Pahsimeroi, Idaho
4 D. auratus blue
5 D. galactonotus pumpkin orange splash back
5 D. imitator
6 D. leucomelas
4 D. pumilio Bastimentos
4 D. fantasticus
4 P. terribilis
4 D. reticulatus
4 D. castaneoticus
2 D. azureus
4 P vittatus