rocks from the colorado river


New Member
Hi to everyone,
My son just gave me some of his rocks that we got from the co. river. These rocks actually look a bit like l/r they have crevices and tiny holes that I guess use to house little critters. We can see some fossiles in them. My question is can I use them for part of my reef wall? Dont know what the make up of the rock is. All I know they are hard as a Rock (Sorry about the punn)LoL...


Active Member
Generally not recommended. You don't know what is/was living inside the rocks, or what the makeup of the material itself is. Having said that, I did once use some flat rocks I found in the woods around my house to frag some corals, but I remember getting slammed for it once I asked about it on here. They are still in my tank now, but I could have just gotten lucky. Again, generally not a good idea.


I also asked the "rock" question and was told most definitely NOT TO use anything that you are not sure of...lots of rocks contain metals (irons, ores)