This product is totally fish safe
Benefits of the professional grade black waterfall foam:
Black Waterfall Foam is a low expansion, high-density foam used in the construction of natural looking waterfalls and streams.
Expanding to fill voids between rocks and liner, this foam directs and diverts water over stones and where you want the water to go. This product minimises time in building waterfalls and streams with its ease of use and fast curing times.
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