Outside River rock cleaning question

[ND1990]

I have a 125 Gallon and I want to add river rock, where I live there is hundreds of tons and I was told I can use them if I wanted. I don’t know what kind of chemicals they used to kill weeds or whatever. 

Is it worth cleaning them up and use them or are they pretty much ruined? Recently the only weed killer they used has been vinegar and water and bleach. Many years back they used roundup. 

I’m in no rush, but if it’s something I can clean how would I go about doing so so make them tank clean/friendly. 

Thanks 

[Griznatch]

 I wouldn't risk anything that was exposed to roundup. Even if it's been a few years, but that's just me. Do you have access to rocks in an actual river? If so, try those and just boil them...

[Hobbit]

As my signature says, I’m not afraid of experimentation 😅 so I would totally use them. Roundup doesn’t persist for years in the soil (if I remember correctly—I did some research on this years ago when trying to decide whether to use it in a corner of the yard). I wouldn’t use anything visibly porous just to be safe. Rinse them really well, and if you want to kill any critters, either boil them or bake them.

Just know that some rocks will raise your pH by adding buffer, the same way crushed coral would. If you’re going for a low pH tank, you’ll want to test the rocks before using them. Rinse them REALLY well and then leave them in a bucket for a week or two. Also leave a plain cup of water out for the same length of time. Then compare the pH.

[ND1990]

On 8/13/2021 at 6:25 PM, Hobbit said:

As my signature says, I’m not afraid of experimentation 😅 so I would totally use them. Roundup doesn’t persist for years in the soil (if I remember correctly—I did some research on this years ago when trying to decide whether to use it in a corner of the yard). I wouldn’t use anything visibly porous just to be safe. Rinse them really well, and if you want to kill any critters, either boil them or bake them.

Just know that some rocks will raise your pH by adding buffer, the same way crushed coral would. If you’re going for a low pH tank, you’ll want to test the rocks before using them. Rinse them REALLY well and then leave them in a bucket for a week or two. Also leave a plain cup of water out for the same length of time. Then compare the pH.

Thanks for the info, I’m not worried about PH. Going to set up a Hillstream loach and Congo tetra tank!