# [Wet Thumb Forum]-mono foam mountain



## KrisL. (Jul 31, 2004)

anyone try using mono foam to build a mountain like structure, and cover it with some hobby cement? would like to know if it migh t be toxic to fish??


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## KrisL. (Jul 31, 2004)

anyone try using mono foam to build a mountain like structure, and cover it with some hobby cement? would like to know if it migh t be toxic to fish??


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## JamesHoftiezer (Feb 2, 2003)

I would assume yes.

In the cases where people have used the foam or similar 'construction' foams they have covered them with epoxy resins to make everything waterproof and to keep any toxins from leaching into the water.


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## Nillo (Jun 11, 2005)

If by mono foam you mean single component polyurethane expanding foam, than yes I have used that before in aquascapes. Although I prefer to use it as mortar to hold rocks together. As for leaching things into the water, PU expandable foam is completely inert and won't leach anything into the water column. From what I understand from people that use it solely for aquascaping tend to paint it or add dyes to it, and this may explain why they epoxy coat it. Also, the epoxy coat will protect the foam from deterioration due to light, or fish. I have hear that the PU foam can fade and get crumbly in high UV light situations, but I have never had that experience since I make sure that the foam can't be seen I never use epoxy when I use PU foam an have never had any problems.

Now if that isn't what you mean by mono foam please disregard the info.


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