Using rocks from outside

[Vanish]

This is just a query on using rocks that I've found when out and about. Where I work I'm able to lay my hands on some rather large and interesting rocks. I made use of some of these when building my pond, and was able to split some to gain the desired look I was after. I'm thinking of using some in my aquarium, but was considering the possible risks of using just any old rock. I do remember many years ago someone telling me to put vinegar onto a rock to check if it contains lime. Could this be the main risk? Obviously any external pollutants could be cleaned from the rock.

 

[dw1305]

Hi all,

I do remember many years ago someone telling me to put vinegar onto a rock to check if it contains lime. Could this be the main risk? Obviously any external pollutants could be cleaned from the rock.

I always use rocks I find, I think you are pretty safe as long as you keep away from quartz with iron pyrites and green slate. Limestone rocks will raise dGH/dKH, but really old, hard limestones, like White Peak or Mendip Carboniferous limestone, hardly give off any bases.

If you want to be sure about a rock (legally collected) beach cobbles are pretty safe, it is only really hard rock that forms nice rounded cobbles.

cheers Darrel

 

[Kannu]

You should be perfectly fine using just any old rock. Give them a thorough clean and you can try the good old vinegar method on a small piece of sample from the rock to check if it will contribute to the water hardness. One other thing I would look out for is that the rock does not have any sharp jagged edges to reduce the risk of fish injuring themselves.

 

[Vanish]

Great stuff. Looks like I'll be busy this weekend - rock sorting

 

[Kannu]

Since you are interested in using rocks, this article by our very own George Farmer may help you How to set up an Iwagumi aquarium | Features | Practical Fishkeeping