How to tell if rocks are safe

[olson78]

I have some really nice rocks I picked up from a beach on the east coast ( an ocean beach ).

I've boiled them numerous times for hours at a time.  Would they be safe to use? Is there a test I can do on them to check the salt content or anything?

[BigDaddy]

If you have boiled them, the only thing you would have to worry about now is if they are calciferous or not.  And then, that's only if you are concerned about the rocks impacting the pH (if you are putting them in an African tank, not likely)

You can do two things

1)  Put the rocks in some "control" water for a while and check to see if the pH gH and/or kH changes after a period of time (up to you to determine how long)

2)  Get some muriatic acid and drip some on the rock.  If the rock "fizzes", then it is calciferous and will be leeching minerals into your tank over time.

[olson78]

Thanks for the advice, I will do that.

[darkdep]

I very recently returned from a trip down east, and brought a few buckets of ocean rock back with me.  Hosed and boiled em, and in they went.  No issues.  None of the rocks I have were calciferous.

[rickster]

:)very cool i did not know that trick with the muriatic acid

[Nerine]

thanks for the info!!
gonna go find some muriatic acid now....

[lucky777]

I started baking them recently @ 350 degrees and then would sit them overnight in bleach/water solution.  Rinse good until you smell no more bleach and they should be fine.


My newest rocks cleaned this way have been in for a month at least without any issues

[busdriver]

Was everyone down east at the same time picking up rocks from the ocean,
just got back from Grand Manan with a bag of rocks, threw them in really scalding hot water a couple of times, let them cool, then in the tanks.
Been like two weeks now and no problems.
B/n pleco's seem to like them as they're always cleaning them.

Busdriver

[Jennywrenn]

I have chunks of white marble behind my house in the woods. Was thinking of getting them for my one tank. Now I know how to make sure they are clean before I start w fish in the new tank.

We also live fairly close to the white marble quarry out by Tatlock and make occassional trips for more rock. They actually drop it at the view point, and you can pick it up. Some small (about the size of an apple) and other stuff just big enough to lift w 2 hands.
Last trip out we loaded 5 garbage cans w small stuff for paths at home and loaded up the rest of the truck bed with larger stuff.
Looking forward to the contrast of dark gravel, white and light rock and brightly coloured fish together.

[Julie]

Jenny, would they be leaching calcium in your tank?

[jdx]

I've used hundreds of pounds rocks in my tank, didn't even bother boiling or testing any of them. I just used those solid ones that appeared to have stayed in the wild for ages. It took millions of year to form rocks and they are exposed to water/atmosphere, I feel little reason to worry about it. Nor did I boil/test the drift woods that I collected fromt the river and lakes.

I don't think my fish should live in a sterilized world any way.

[Jennywrenn]

I don't have any in a tank yet Julie. I was thinking about it for the contrast and beauty factor, and thanks to the info to test rocks, I can now check before I do anything of that sort.
They might, they might not. I don't have a tank set up yet anyway, so I may do the 'test in a tank' wihtout fish first, to see what happens to the water etc.
I live in the country and have hard water anyway, so don't think it's going to affect it that way.
I think limestone would be a worse leacher than marble, as marble has been subjected to the heat of the land and compressed into incredibly dense material.
Jenny