Can you put grow crystals in a aquarium?

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bluebird42

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You know those things, it's the rock and you put it in water mixed with the powder and it grows crystals. I think those look cool, if I grow one and clean it off real good afterwards, will it leech chemicals into my aquarium or is it just a rock by then? Not doing this until it's confirmed completely safe, of course.
 
Personally I wouldn't do it. I'm not sure of the components of the crystal and I wouldn't be happy with a problem later down the track if there was something in the crystal that was bad for life.
 
Yeah. Would love to find a natural rock formation that looks like that. Gemstones would be pretty in a aquarium.
 
You know those things, it's the rock and you put it in water mixed with the powder and it grows crystals.

Short answer is no.
 
Go to a crystal shop, yes boogy woogy hocus pocus stuff, and buy a crystal. They come in various shapes, sizes and colours. Alternatively there are plenty of artificial crystals around now and they are made from plastic resin and are safe. Just give them a good wash before adding to the tank to remove any dirt.

You can even check with your petshop. Years ago one of the suppliers was bringing in plastic crystals for aquariums. They might be able to order you some in. Or check out places that sell fake gems and jewellery.
 
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I just remembered I had some natural rocks and crystals...the black ones are obsidian and the others I don't know what they are? Does anyone know if it'd be safe to use these?
I read somewhere else that obsidian is OK as long as you're really careful to make sure there's no sharp edges. My stuff is just more like a rock than glass and doesn't seem to break easy or have any sharp edges. So I put it in making sure that nothing was sharp where it could hurt my snails when they slither across them :D
 
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Can anyone confirm if those clearish rocks are quartz? And I believe the darker brown one might be tigers eye? I want to make sure before putting it in my aquarium...If you need a better picture I can provide that
 
they all look fine, just watch the sharp edges. Snails don't normally have an issue but fish can get cut up on sharp rocks.
 
:D Thank you for the help! I will be very careful. Thank you so much Colin since I have joined you have consistently helped me and I really appreciate that.
 
TEST THE STONES.

Get a small piece of tupperware and fill it with water, just enough to submerge the stone. Test the water's PH. Then add a stone (just one), and let it sit for a few hours. Test the water's PH again. If the water's PH changed, do not put that stone in the tank.

Generally Quartz is safe. Amethyst too. As a general rule, the darker stones are more likely to be toxic in a fish tank, but amethyst can be an exception to this as it's a quartz based stone.

In my community tank I have one Amethyst heart and one Quartz "healing crystal".

There's another test that you can do with the stones, where you use an eye-dropper to drip fluid on the stone and see if it bubbles or not, but I can't remember what fluid is used in that test. I want to say vinegar, but I feel like that's wrong. If anyone knows what I'm talking about, please clarify. It's the same test you use on rocks you find in the wild to see if they're safe for your aquarium.

I would not put a geode in the tank, though, as the crystal itself may be safe but the layers of stone it grew in may not.

As for the grow crystals.... no, just don't do it. Often times those are just salt crystals and food coloring.
 
Its not just about pH. Some rock contains minerals and metals which can be harmful or poisonous when they leach out.
 
they all look fine, just watch the sharp edges. Snails don't normally have an issue but fish can get cut up on sharp rocks.

You know this for a fact DO YOU? NO? then don't say they are safe.
 
I read that crystals are ok but rocks aren't. I took out the tiger's eye and left in the rock crystal and amethyst. If anyone knows if I'm right about what these rocks are and/or the safety of them for sure please let me know. Thanks.
 
Tiger's eye regularly gets used in aquariums in Asia and I have seen it in tanks in America.

Crystals were kept in my dad's and cousin's tanks for years and the fish were fine, my dad and cousin loved the energy from their crystals.

Slate and granite are fine.

Limestone and sandstone are porous rocks and are calcium based. These 2 types of rocks will cause the pH and hardness to increase. The pH will go up quickly and can get to 8.5, whereas the hardness will only increase slowly. Limestone and sand stone were used in my tanks and tanks in the shops to stop the pH dropping rapidly. They are a natural buffer.

To see if a rock is limestone or sandstone, look for a white rock and rub it with a metal nail. Limestone and sand stone are both soft rocks and are easy to cut and scratch with metal objects. They are also white when clean. Then pour some vinegar on the rock. The vinegar is very acidic and has a pH below 5.0. If it bubbles up and creates a white foam, then the vinegar is reacting to the calcium in the rock. And that is either limestone or sand stone.

Sand stone looks like lots of grains of sand have been stuck together to make the rock. Limestone looks more like a white rock and is primarily lime sand compressed together. Sometimes you get sand mixed in with the lime sand and you can have limestone with some sand in it.

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The only reason the rocks should cause a problem is if they have been contaminated with a harmful chemical. eg: they came from a farm property and were sprayed with weed killer.

Some crystals get glued together to make a larger crystal. This is usually done by the collector who finds a pocket of broken crystal and glues the pieces back together to form one large crystal. The large crystals are worth more than smaller pieces. If they use Superglue to glue the crystal back together then that is fine.
Superglue is regularly used by marine aquarists to glue pieces of coral to limestone when they are culturing live stony corals like Acroporas.

If you really want rocks, check out round river rocks at a nursery, but wash them well before use in case they have been contaminated with anything. You can buy bags of round river rocks at hardware stores and petshops. Again wash well before using.
 

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