Is butyl rubber caulking fish safe?

[Grandpa]

I am making my own bio filter and have some butly caulking. Would this be
OK to use?

Thanks.

[George]

"Grandpa" > wrote in message
...
>I am making my own bio filter and have some butly caulking. Would this be
> OK to use?
>
> Thanks.
>

My rule of thumb with sealants is that if it doesn't say it is safe for fish,
don't trust it. I would use a sealant approved for the use. Aquarium sealant
should work fine, as long as you let it dry completely before using the filter.