who knows about rocks?

[shrimpstan]

hi SKF,

does anyone know which rocks are safe to use in CRS tanks?? and something reasonable on the pocket :P

really appreciate any recommendations :)

cheers,

shrimpstan

[2OFUS]

Any rock u get u should pour vinegar on them ... If the vinegar sizzles then the rock will effect you water parameters

[MrShrimp]

Wow that's a first, never heard of that method before. Gotta try it on my rocks :)

[Squiggle]

Yeah, vinegar is the best way :encouragement:

[Gareth]

At the shop I work at we use pool hydrochloric acid. It REALLY sizzles :)

[torface]

Vinegar is not really a strong enough in my opinion. You really should use 10% hydrochloric acid if you can. However, muriatic acid can also be used if you cant get HCl. Even then the test isn't fool proof as the rock can have veins, nodules or patches of carbonate. So make sure you test any different coloured parts. Also it's a good idea to scratch the rock with a steel blade before testing with acid.

The acid test also won't tell you if there are any heavy metals in the rock. If you're buying from a lfs, they're more than likely going to be ok in this respect, but something to bear in mind if you're sourcing rocks from elsewhere.

And I'm not sure how it affects shrimp, but rocks can also leach things like phosphate, iron and acids into the water.

things like quartz, quartzite and slate are generally ok.

[Squiggle]

Straight from the miners mouth, couldn't get any better advice than that, thanks torface :encouragement:

[torface]

LOL :)

I don't intend to scare anyone though. I just think people need to be more aware that testing with vinegar isn't a sure fine way of knowing a rock is safe for a shrimp/fish tank :)

Many people have taken rocks from work thinking "oh that's pretty, i'll put it in my fish tank" which has ended up in dead fish. And those rocks will not have fizzed with vinegar....

But like i said, if you're buying from a LFS, chances are the worst thing thats in it is carbonate so testing with hydrochloric/ muriatic acid or vinegar will be able to tell you if it's ok or not.

[shrimpstan]

yeah thanks garry will keep that method in mind :)

just to be sure... are there actual rock types that are for sure safe.. along with quartz and slate.. any others??

i think a comprehensive list would be sweet :) pitty i dont no much about geology.. 'elbow jab torface in the ribs' :P

[torface]

LOL

I try to avoid talking about geology cos i dont want to be responsible for anyone putting the wrong rock it their tank, so i take no responsibility for any rocks put in tanks! :P :)

It's hard to give a comprehensive list of rock types that are safe because in theory, any rock type can potential contain metals. For example, quartzite is generally inert but the Mount Gordon Copper deposit is hosted in a quartzite. A chunk of that would kill your shrimps pretty sharpish.

However, we're probably talking about rocks you can buy, right? It's unlikely that a rock you buy from the LFS or from your local garden centre will contain copper/ lead/ zinc (although not an impossibility). You also have to bear in mind that most places wont even know what the rock type is. I recently bought some described as "Tibetan Mountain Rock", the guy couldn't tell me anything else about it. "Tibetan Mountain Rock" isn't a proper name for a rock. "Lava Rock" isn't either for that matter. So the best thing to do is test it with acid (or vinegar if you dont have acid) and make sure you test any different bits of the rock that are a different colour... And dont forget to rinse the acid off well!

Rocks that are *likely* to be ok:

Slate/ shale

Most igneous type rocks (Basalt, Granite, Rhyolite, Andesite etc etc etc) - check they dont have any veins that fizz!

Quartz (and it's various types e.g. rose quartz, citrine, amethyst, jasper etc)

Chert

Quartzite

Diamonds (LOL)

Here is a good rule of thumb:

If the rock is red it contains iron, whether or not it'll leach depends on the rock and if it is harmful for shrimps, i dont know... personally i wouldnt risk it.

If there are any BRIGHT colours, i'd give it a miss (unless you know its a quartz variety, which you will know because you cant scratch it)

If it fizzes with acid/ vinegar it will raise the PH of your tank. Make sure to scratch it before adding the acid... (dolomite wont fizz unless it's scratched)

In general if it looks boring and doesnt fizz, it should be ok! LOL

[jrc693]

a lot of people go to the nursery in canley vale, they supply both natural slate and honeycomb rocks. not to expensive either.

if u want a safe bet, those rocks are perfect just need to give them a good scrub.

Have had both those rocks from there in my tank for months with no complications

[CNgo2006]

a lot of people go to the nursery in canley vale' date=' they supply both natural slate and honeycomb rocks. not to expensive either.

if u want a safe bet, those rocks are perfect just need to give them a good scrub.

Have had both those rocks from there in my tank for months with no complications[/quote']

+1 and it is about 2 mins from where I am!

[BlueBolts]

torface, why try to hide your talents ... :-), perhaps you can start a new thread, add some pics etc, and we can ask the mods to add it as a sticky ? Great info...but appreciate your comments.... You take no responsibility, thanks for the info.

[Squiggle]

+1 totally agree, STI-CKY! STI-CKY! Very cool write up torface, well done :encouragement:

[torface]

Yeah i've thought about doing it before but havent found the time yet. Problem is, there's so much to know about rocks... it can get very very complicated lol :)

[BlueBolts]

C'mon torface, for the love of SKF...:-) do simplify it for us common folks, it'll be a great sticky as so many hobbyist ask and have wondered..... Otherwise squiggle's gonna be on your back !

[Squiggle]

Yeah, what he said! STI-CKY! STI-CKY! There's not many as qualified as you are torface, c'mon where's the love? Lol

[shrimpstan]

yeah thanks torface i was hoping it could be a sticky too!!! good write up.. its not something that gets talked about all that often. jus figured if just one descriptive article could save lots of shrimps lives its worth it! looks like im gonna go for some honeycomb rock.. looks pretty good and heard of a few ppl that use it.

thanks again torface!! :)

[torface]

No worries.

I'll see if i can type something up soon. Probably when im bored at work lol

[shrimpstan]

sounds like a plan :P

cheers bud

[Squiggle]

Lol, should do it when the head honchos leave & you're in charge :victorious:

[torface]

LOL yep that's when all the mischief happens ;)

[Squiggle]

Ooooo, I'm excited to read what you come up with, should be very interesting :encouragement:

[torface]

LOL Squiggle... rocks are rarely interesting :P

[Squiggle]

Lol, that may be so but rocks that don't kill shrimpies are & knowing which ones they are, what to look for & how to test them is as well :victorious: