What effect does Copper pipe have in a freshwater aquarium?

[MnGGx2]

I pulled a water feature with a piece of slate hanging off of copper tubing that I wasn't using and put it in my aquarium as a decorative piece. Someone asked if this would hurt the water. I haven't noticed anything on my parameters and I've been using it since November of 2009. I have a 29 gallon tank with dwarf rainbows and cories and one platy. Does anyone have any info on the unseen side effects of copper in a freshwater aquarium? I am just wondering if I should re-purpose it in the garden or something.

 

[Crepe]

Large amounts of copper can kill algae, shrimp, snails and other invertebrates and non-vascular plants. Otherwise it's harmless. Residue from copper pipes isn't generally enough to do any harm and can be dissipated with water changes.

 

[MnGGx2]

Thank you. That is good to know.

 

[Laurence]

Small amounts of copper may not affect the water quality, but it is better to avoid the metal. Copper corrodes, and even small amounts of copper can adversely affect the plants and the beneficial bacteria in your tank and filter system. Your best bet is to elminate the metal entirely and use it for something else.

 

[JohnPaul]

Copper is incredibly toxic to inverts, including freshwater shrimp, crays, crabs, and snails. Indeed if you glance at any of the "get rid of snails"-type medications in the aquarium section of your LFS, you will see that most (if not all) of them use copper as the active ingredient.

The issue here is the fact that copper ions will slowly leach from the copper tubing into the water--the more acidic your water, the faster the leaching. Once there is copper in solution in your tank, it gets absorbed by the silicone sealant and then slowly re-released over time. So 5 years down the road, even if you haven't had that piece of copper in your tank in years, you might decide to add some ghost shrimp or whatever, and the next morning wake up to a bunch of dead carcasses. Copper in the aquarium is kind of like PCB's in the environment...once it is there, it takes forever-and-a-half to get rid of it.

I don't think fish are sensitive to copper in the same way that inverts are, so if you are 100% positive that you are never going to want anything other than fish in the tank, you are probably in fine shape.