Aren't Rocks....Just Rocks??

[Tayeloquin]

You should never boil rock if it's the wrong rock it can explode. DO NOT BOIL ROCKS

This is what I was thinking. Boiling rocks? I believe that it has something to do with the water content in some rocks. I'm not sure.

After doing a search, it seems this is true. I don't know if it's the rock type or what is a determining factor for this.

Honestly, I would love to know more about this as well if anyone has more information.

 

[Loach23]

Rocks are porous to various extents and will have a moisture content. When you place a rock by the fire, you're heating the internal water. If the water in the rock turns to steam faster than it can escape, pressure builds, and the rock can come apart with force.

When you boil a rock, even though there's no fire, you're still applying heat, and that can cause the water inside the rock to turn to steam with the same end result.

 

[Tayeloquin]

Are there certain rocks to avoid? Or is it just rocks in general?

 

[Loach23]

Drop vinegar on the rock if it fizz or created some bubbles then they are no good if the don't. Then it's a good rock for your aquarium

 

[Tayeloquin]

Okay, I get that test.

Is there another non-chemical way to sterilize the rock? I've seen some posts on other websites that state to bathe the rock as opposed to full out boiling it. I guess that would still be chancy though...

 

[Loach23]

I would just wash and scrub with some hot sink water

 

[Shadowraven]

I have heard what loach has said before, but haven't seen it happen. That doesn't mean that it can't, just that I've never seen it. I've done it numerous times without a problem, but I suppose it could. I would think it more likely to happen if you dropped a cold rock into hot water. I always allowed mine to heat up with the water. I even use heated rock for cooking and they get VERY hot.

If it would happen, I think that it would be much more likely to happen to a more porous rock like sandstone. The pores in it are very small and steam might get trapped in there. It's very unlikely to happen with scoria because it is a rock with very large pores.

Rocks should be sterilized before adding them to the aquarium. I've heard of people letting them soak in bleach for a few days. That will kill anything on them and may be an option if you're concerned. Since bleach is chlorine I suppose you could rinse them in water conditioner before you add them. I'm not too sure how likely it is that you could neutralize all the bleach on the rock, especially if it was porous.

You night also be able to let them soak in water that is just short of boiling on a low heat. It will probably be almost as good without the concern that boiling may cause you.

I'll check further into what loach has said and get back with you folks.

 

[Shadowraven]

Are there certain rocks to avoid? Or is it just rocks in general?

Avoid most sedimentary rocks like limestone, calcites, chalks, marble, shale and the like. Sandstone being the exception as it is usually safe but test it first. Most metamorphic rocks are good choices like slate, granite, gneiss or hornblende. Many volcanic rocks like scoria are OK too.

I consider granite, slate and scoria to be the best choices, but they certainly aren't the only ones.

 

[glassbird]

Putting rocks in the oven to bake them for sterilization purposes is also a bad idea, for the same reasons as boiling. I have a dent in the back wall of my oven. I have never had the nerve to tell my non-fish keeping roommate how it got there...

And +1 to ShadowRaven for supplying us with actual names! Good list!

 

[glassbird]

...forgot to complete my thought. Many (not all) of the gravels in pet stores have been colored. The better companies use the same colors year after year and seal the color in...Estes, for example. This means that if you get a bigger aquarium in 20 years, but want to keep using the colored gravel that you have been using (and need more of it), you can get it and it will blend.

I just redid the landscaping in my 75 gallon and needed more "Bits of Walnut". One special order with my LFS, and my tank is looking good! Some of my original gravel is almost 25 years old.

 

[Tayeloquin]

@Shadowraven: Thank you so much for answering my questions before I just went out and picked up rock and hoped for the best. I used to collect rocks for a hobby and can usually tell the differences between them. I think I'll use a bathing/bleaching process to sterilize. Though I'm still not comfortable with using a chemical to sterilize. Such a noob to fish keeping, I'd be worried that I'm hurting my guys.

Agreed with Glassbird, +1 for supplying us with names!

@Glassbird: Oh dear! I don't think I would have admitted that either. Though it's a husband that I have to explain things to. I'm always getting into something one way or another, and he sees right past the "who? me?" expression.

And thanks for the tips on gravel. The type that I use was just from Walmart, but it's a natural looking stone. Browns, blacks and tans. They only sold it in 25lbs bags, and with a 10 gallon tank, I have PLENTY left over...lol. "Bits of Walnut" does sound very pretty though.

 

[Shadowraven]

@Shadowraven: Thank you so much for answering my questions before I just went out and picked up rock and hoped for the best. I used to collect rocks for a hobby and can usually tell the differences between them. I think I'll use a bathing/bleaching process to sterilize. Though I'm still not comfortable with using a chemical to sterilize. Such a noob to fish keeping, I'd be worried that I'm hurting my guys.

Agreed with Glassbird, +1 for supplying us with names!

You're quite welcome. I'm glad to help.

Also, just so you know, I've almost completed my research on the best way to prepare rocks for the aquarium. loach was so adamant about not boiling them that I decided to do some research (similar to my hydrogen sulfide thread) to ferret out the truth of the matter. Hint, it won't involve any chemicals. I'm likely to be posting it Friday evening if you're interested.

 

[Tayeloquin]

I definitely am interested!

I also did manage to catch the hydrogen sulfide thread too. You are entirely well versed and thorough when it comes to research. You think I might be able to bribe you to write/research a few papers for school for me???

 

[Shadowraven]

LOL. I'm afraid I'm well past that now!

Could never afford to go to college anyway.

 

[glassbird]

Re: the dent in the back of my oven from baking a rock...I just try to grateful that the projectile part bounced off the back wall, and not the front "wall"...since the front has glass and probably would have broken dramatically.

As the chunk carromed around the inside of the oven, it also knocked the heating element loose from the top. But that just plugged back in, so no harm done.

I was impressed that the new gravel matched my really old gravel. There is something to be said for quality, although when I bought the original bags of the "Bits o' Walnut' I never imagined that I would still be using it 25 years later. But I was working part-time at a fish store while going to college...and I went with "the good stuff" since I was getting my employee discount on it anyway.

I just realised that I am blathering about "high quality gravel". I think I need some sleep...now.

 

[WendiDell]

No, not live rocks, just the gravel rocks from a pet store. The stuff in bags on the shelf. I guess I don't understand what makes them not leach minerals and stuff into the water, but if I get rock from a landscaper I'm told it does.

A lot of the aquarium gravel is clear coated to prevent it from leaching minerals from the water. Except in the case of Cichlid gravel, it actually adds minerals and helps to stabilize your pH at the higher 8.2-8.6.
The clear coating also protects against any unwanted passengers being added to your tank. And there is no gravel dust, as a bonus. No dust isn't a requirement but it is helpful. The aquarium gravel is processed and sealed for the safety of the fish.
That's why it costs a bit more.
It also helps to shop around for the best price. I only paid .60 cents a pound for my tank gravel.

 

[Irish.OG87]

i just picked up really nice rocks down by the river, how would i know which rock is which i.e like if its sandstone or granite etc i cud do both methods to clean them like the bleach clean or the warm water idea. Just dont wanna mess my tank up.

 

[Shadowraven]

I wish that I could give you an easy answer to that, but short of having someone with who knows rocks, I'd say that you'd need a field manual to identify them.

From having studied geology I can recognize most common types of rocks and minerals, but it's kind of hard to describe to someone else. The field is just too wide. Sometimes I can do it from pictures.

The vinegar test is the best to use to make sure that the rocks won't effect your water. Sandstone is fairly easy as it's often somewhat rough and gritty. Inappropriate types like limestone will probably be somewhat slick to the touch and a greenish-gray to light gray in color.

Try this link. It may help you.

 

[Tayeloquin]

Well geeze.

I have a paleontologist friend that I'm sure that I can get to come and read the thread. She may give a general description of the rocks that we're looking for, maybe. I know that the vinegar test isn't fool proof.

I've known her all my life, and I don't know why I didn't think of her sooner.

 

[Mr. Limpet]

You should never boil rock if it's the wrong rock it can explode. DO NOT BOIL ROCKS

It may have to do with "how" you boiling them. I bake/boil rocks and the trick to what you're talking about (moisture, etc inside the rock) is to put the rock in as you strart the heat, not after it's boiling/oven at temp. Kinda like adding oil to a skillet, put it in when it's cool and no explosive sizzle, after it's hot and you get burned.

I'm soaking some lava and river rocks in a 10% bleach solution right now. After it's done and been rinsed a few time in our toilet tank, I plan to bake the lava at 350 for an hour or so and boil the river rock at med/high for an hour. This is the 4th time (more?) I've done these same processes. Of course I learned this after my first attempt at sterilizing rocks .