I haven't seen any bad (dead fish) reviews on Envirotex yet and they use it with discus and reefs (they're sensitive). I'm finding it hard to find a MSDS on the combined material... they have it for each part but not the cured stuff. Rather odd. I did find a post where it cracked the bottom of someone's 240 or something gallon tank when they filled it with super cold water. At least they had insurance and the tank cracked with only a few gallons in it!
I think I'll only use it on stuff that I can remove from the tank just in case something goes wrong. Not that I think something will go wrong, my goldfish aren't all that sensitive. I change the water all the time anyway. I wont seal the cement with it (since I will be siliconing it into the tank), I'll just have to color the cement, use real rock for the stones in the tree, and silicone it together. I wouldn't feel comfortable having 340gph water running over this stuff non-stop for a couple years or more but I'm ok about using it as a hard sealant on items in my tank where the flow isn't a concern.
Now I'm not sure how to seal the hollow parts of the trees.
The output hose will point down into this area behind the left tree. It will fill up the "bucket"...
and flow out the hole and through the rain gutter hydroponic garden...
Out this hole and fill up this second "bucket" in the right tree...
and flow out over these rocks. Hopefully I can align them right so there isn't a lot of water noise.
Any ideas? Maybe some sheet plastic that I can silicone in place? I have some that we used to use for a diy slip and slide, could that work?
