Rocks Safe for Aquarium?

[dxs2104]

I could use some help identifying some rocks to make sure they are safe for to put in my tank. I grabbed them from a freshwater river in Vermont. Pretty certain the #8 rocks are Fe2O3.

 

[Lowryder]

Best way to test them is with diluted hydrochloric acid i.e muratic acid. If it fizzes and bubbles then they are no go. Also, PH down will work for testing.

 

[logansmomma1228]

Maybe this thread will help you out: http://www.aquariumadvice.com/forums/f12/river-rocks-rock-test-130944.html

 

[dxs2104]

Ok so I boiled all the rocks for a few min, let them cool down, then tested them with toilet boil cleaner (HCl). It worked really well actually, turned blue to white when reacted with limestone (or anything other base)

Good:
#1, #4, #5, #6, #8 small, #10, #11, #13, #14

Bad:
#3 (mostly good, but back corner reacted)
#7 (must have been limestone, reacted everywhere)
#8 (top was good, back must have been covered in limestone)
#9 & #12

Didnt test #2

 

[Lowryder]

Ok so I boiled all the rocks for a few min, let them cool down, then tested them with toilet boil cleaner (HCl). It worked really well actually, turned blue to white when reacted with limestone (or anything other base)

Good:
#1, #4, #5, #6, #8 small, #10, #11, #13, #14

Bad:
#3 (mostly good, but back corner reacted)
#7 (must have been limestone, reacted everywhere)
#8 (top was good, back must have been covered in limestone)
#9 & #12

Didnt test #2

I am worried about 1 thing. That the toilet bowl cleaner had some type of detergent and will be harmful to your tank.

 

[dxs2104]

I am worried about 1 thing. That the toilet bowl cleaner had some type of detergent and will be harmful to your tank.

Didn't even think of that...

Any chance I could wash/boil them enough to use? I used small drops of the stuff diluted (happen to have a couple pipettes). Already tossed the #8 one, was very porous.


Edit: Playing it safe. Tossing them all. Lesson learned.

 

[taylorodw]

If you didn't throw them away, and you want to use them, I would run scalding water over them and scrub with an old tooth brush/wire brush/some sort of abrasive surface. Then rinse one more time, and go.