Hi guys: Probably a elementary question but hear goes. I have a PVC ball valve controlling a return line to my tank from the sump. The PVC valve seems to turn hard and is difficult to adjust. I have a brass gate valve that is much more accurate in flow control. This being said can I use just this one valve in the system? Is it unadviseable to do so? As always your response will be appreciated.......Dass

I'm no expert but brass is made of copper and zinc. Copper in a reef is bad, bad news. Not sure how alloys fall into this, though, since they tend to have different traits than their component elements. Of other concern is what lubricant is in the valve, if any.

You can get PVC gate valves that are definitely reef-safe, but I'm not sure what size application you're talking about.

Im no expert eitherr but i would say copper is bad. With a quick google search for copper + reef tanks i found that some people say no! and some people say been using it for years and no problems. but dont take my word for it. lol I would say no to copper. It has all the right elements to make a good tank go very very bad. Im sure the salt water reacts with the copper causing further problems as well. I would stick with PVC. :)

Thanks for the info guys. I will not make any hasty decisions on this one...........Dass

I bought a pvc gate valve on eBay. Check there.

Copper kills, but most metals can become toxic in a reef tank from what I understand.