How to test if rock is safe for the tank????

[Dave_2133]

I've had some rock from my local fishing lakes i just wanted to know the safest way to test if is ok to put in my tank.

I've heard that you can put vinigar on it and if it bubbles then its not safe, but dont know how true this is

[palaeodave]

If it effervesces with acid (bubbles with vinegar) then it is made of calcium carbonate and so will slowly dissolve in your tank water both increasing the pH and hardness. Probably not what you want. Vinegar is pretty weak acetic acid, so you might want to watch carefully. Make sure you rinse it off thoroughly if you're going to then put it in your tank.

[sophie]

but if you're in staffs and you share the brimingham water supply (do you?) then adding a buffer wouldn't hurt. upping the hardness and keeping the pH stable isn't a bad thing at all round here!

if you're worried about bugs you could either stick it in a bucket of milton overnight then rinse, rinse, rinse and dechlorinate or try a low oven for a few hours; but depending on the rock that could (fairly slim possibility) result in it going BANG...

[tglassburner]

I boiled all the rock for my rivertank

[chefkeith]

I used a TDS meter to test most of my rocks. I put each type of rock in a seperate container and filled each one RO water. Then I'd test the water with the TDS meter after about 1 week. I learned that all of the rocks I had tested were leaching something into water.

[Killfrenzy]

Say, there wouldn't happen to be any slag in the rocks you tested? Smelting byproduct, somewhat glassy/obsidian look, dark blue/green color (around here, anyways). It seems inert, but I don't exactly have a TDS meter on hand...

[Dave_2133]

I went to redesign my tank today with the new rocks i got, but sadly when i was cleaning them and doing the vinegar test all of them bubbled like crazy so it looks like i'll have to go the DIY/Gardens centres to buy some now. But some of them only bubbled slightly and i had to use a magnifing(sorry bad spelling) glass to see it, so would these b ok to use???