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using found rocks, what do i need to do?

880 Views 8 Replies 7 Participants Last post by  Diana
Can i just boil them? which are okay to use vs not?
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I'm sure others will add to this.
Boiling can cause them to explode, more commonly to crack. 175F is good though.
Drop vinegar on them. If it fizzles/foams it is not good.
Actually I have never done either but that is taking chances.
Do not boil them, some warn that air pockets in the rocks can expand and explode. Instead, give them a good scrub and rinse. Then put them in a bucket or sink and pour boiling water over them.

If you want to be doubly sure, sanitize them with bleach water, then rinse them and let them sit in water with dechlorinator for a few days, change the water a few times.

I have only ever poured boiling water on mine and have no issues.
I never bother with boiling rocks.
Just clean the dirt off them.

The vinegar test is OK, but an even better one is to put the rocks in a bucket with some of the water from the tank. If the tank water maintains the same GH, KH, TDS and pH in the bucket with the rocks, then the rocks are not likely to affect the water when you put them in the tank.
I got 3 stones (I think vinegar) from the local lake and placed them in our dirt tank. All I did was pour a little vinegar on each and boil them for an hour.
I've never figured what the boiling would do for rocks. One of the items you don't want to put in the tank is a rock that has oil on it. Boil the rock and what do you get? The oil is still in the water so you get a rock that has been boiled in oily water!
An overnight bleach soak is the way I go for all things that I want safe for the tank. Much easier and cheaper. You may not have a pot big enough for a big old stump but it is easy to find a plastic trash can that fits. Fifty cents worth of bleach will clean anything smaller than a cow and that is much cheaper than the fuel you would use to heat the water.
While worry about rocks is a bit overboard when you are using it in a tank with dirt, a soak is simple.
Put the rocks in a container, cover with water and add a 1/2 cup or so of cheap bleach, No scent is preferred, let it set overnight so that the bleach can have a chance to eat through any hard shells like snails, etc. Next day take it out, rinse it a bit to get the major bleach off and then let it dry totally so the chlorine has a chance to gas off.
Then you can use the rocks with the good feeling that they are just as clean as your dinner plate. No little hidden mysteries to sneak up on you.
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Boil all you want, the rocks won't explode, that's a myth that's been floating around for a while.

The thing that could cause a rock to explode is baking one with moisture inside it. In that situation, the moisture converts to steam, causing the rock to explode. This won't happen by boiling it, because the temperature is controlled by the water.

It's the same reason popcorn explodes from a little kernal into a great big puff - it's the moisture in the grain converting to steam at high temps.

Also the same reason eggs explode in the microwave, but not when you boil them.

Anyways, as harmless as boiling rocks is, like PlantedRich, I don't see it being worth the effort. I'd probably just soak them a bit and scrub them with a brush.
This is an area where my feelings have evolved over time. When I first went at adding things to the tank, I really overthought the whole process. As I moved through keeping cichlids, I still tried to sterilize things. But now, I'm adding dirt from the backyard to the tank and wondering just how much worry there is to adding a bit of dirt hanging on a rock or some wood. If I pulled something out of the local creeks, I might go for bleach soaking just because I hate snails and they can ride for days without dying. But for just plain old dirt, I got a feeling it is no worse than the backyard dirt.
Besides that I really enjoy the cool white spots I get when I get sloppy with the bleach!
But now, I'm adding dirt from the backyard to the tank and wondering just how much worry there is to adding a bit of dirt hanging on a rock or some wood.
Exactly! I scrub off the worst of it and use the rock or wood.

I understand bleaching if it came from a wet location (pond, stream)
Or a few soak-and-water-change if it came from a salty location (like the ocean).

But stuff that is just lying around... it has been alternately wet and dry so many times that it seems safe to me. Just a bit dusty.
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