This is a reef lake systems sump. I have never used it, so I can't vouch for it. it also has a refill float plumbed into it. It is missing the media, and the gaskets at the top piping to feed the box are old, but the sump itself appears to have no cracks. It was used by one person for several years on a fish system, so it may, or may not have had copper treatments run through it, but it is ...