Rocks From The Dollar Store?

[fry_forever!]

Hey guys! I went to the dollar store today w/ my friend, and I found these beautiful smooth "river" stones. I thought that I could get them for my aquariums, because they were very pretty. The weird thing is, there's still dirt on some of them. If you scratch at it w/ your nail, it comes off.
And they smell like dirt.

So, my question is, would I be able to put them in my tanks if I washed them really well w/ hot water?

Here are some pics:







Thanks in advance for any help!

 

[Tolak]

As long as you test them with a bit of vinegar to make sure they don't fizz they should work.

Most of my rocks are from a landscaping outfit, pennies per pound when you drive up in the dead of winter. I have a couple tons of river rock on the side of my house, landscaping grade. I regularly grab a handful to weigh down box filters. Rinse with tap water, they are good to go.

 

[fry_forever!]

As long as you test them with a bit of vinegar to make sure they don't fizz they should work.

Most of my rocks are from a landscaping outfit, pennies per pound when you drive up in the dead of winter. I have a couple tons of river rock on the side of my house, landscaping grade. I regularly grab a handful to weigh down box filters. Rinse with tap water, they are good to go.

Thank you very much for the info! I never knew you could test it that way!

So, what does it mean when they fizz?

 

[Tolak]

http/www.fishforums.net/index.php?/topic/55806-rocks-for-use-in-the-aquarium/

If they fizz you risk leaching calcium. This will increase hardness & usually pH. Some fish like this, many don't.

 

[fry_forever!]

Oh wow! Very interesting info! I'll test them if I can find the vinegar.....

Anyhow, I'm pretty sure it will fizz, because when I put that rock in my aquarium, the ph went up. Oops.