Hi Kd67
Copper is extremely toxic to animals and plants alike. Ionized copper is a common ingredient in lots of medicines because of its ability to kill and control parasites and pathogens, but it can also be lethal to fish. True, you're talking about using copper metal and not copper solution, but the line is too fine to consider innocuous.
Honestly, I've never heard of anyone using copper pipes for caves, but there are so many other options available for home made caves (
Home-made pleco spawning caves), not to mention more and more commercially available cheap clay caves (e.g., plecocaves.com), I don't know why someone would try copper pipes... I wouldn't risk it even with common BNs!
If you know something about people using copper caves successfully, I'd be interested to learn, but I don't think I'd every try them myself.
Proceed with caution (actually what I want to say is, "RUN THE OTHER WAY!," but I'll restrain myself).
Kd67 wrote:Looking to create smaller sized caves for BNs but would like something that blends in better with the driftwood than pvc or square stone caves. Thanks for any info.
A much better solution is
bamboo pipe poles. In the USA, you can buy 6-8 foot lengths of 1", 1.5", or 2" diameter bamboo poles at garden stores or hardware stores (I buy mine at Orchard Supply Hardware. A web example is:
http://www.gemplers.com/product/217552/ ... uper-poles). A 1'-2" diameter pipe costs less than $10, and you cut it yourself with an ordinary saw - no fancy tools needed. Depending on the number of "nodes" (bumbs/joints) along the pole, you can get about 6-7 caves out of one pole, plus you'll also have some left-over pipes (open at both ends) to provide additional hiding places. When choosing a pole, pick one that has a node very close to each end of the pipe. That way, you should be able to cut one extra cave from the pipe.
When I buy the poles, I inspect them and I avoid poles that have lengthwise splits along the bamboo. This is strictly for personal preference and it shouldn't harm the functionality of the caves as long as there's only one split, even if it's big and even if it runs the length of the bamboo. This is because when you put split bamboo in water, the bamboo expands and warps back into its original shape, closing the split and making the cave good. That said, if there are two or more parallel splits, that is bad because when you cut the bamboo to length, a portion of the bamboo may fall away, creating a space that cannot close and then your cave is not a cave.
After I find good bamboo pieces, I cut them in 4" to 7" lengths, then I boil the pipes before placing them in the aquarium. My plecos love them, and I've had plenty of spawns in them (BNs and clowns). New bamboo caves will slowly start to peel or delaminate its outer and inner linings. When I see this i remove the caves and rinse them under running water to flush out these peels, then put the caves back in the aquarium. After they peel once, they typically never do it again.
Cheers, Eric