# Hawaii's Black/Red Cinder



## Rond (Jan 5, 2005)

Does anyone know if Black/Red Cinders is safe for aquarium? Are black or red cinders a type of volcanic rock? Is it basalt? I tried looking at the package what type of rock it is or where it came from but it didn't have that kind of information. The package is called Hawaii’s Island Supreme Black Cinders. I guess the Hawaii's Island Supreme is the company who distribute this kind of product. The gravel is very porous and light; it looks like volcanic rocks but I'm not positively sure.


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## Wasserpest (Jun 12, 2003)

First you need to test if the stuff is buoyant. If it has too much air in it it will swim on top, and you can try a down-under tank with light from the bottom.

Second, you can do some testing where you let a bunch of it sit in a glass with a little destilled or tap water a few days and then test pH, kH, GH, and stuff.

Third, you can test if it is toxic with some ghost shrimps in a little tank.

Other than that... It's hard to say if the rock you have is safe or not, since it probably isn't made for fish tanks.


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## ANUBA (Jun 14, 2003)

Randall,
I belive there volcanic, they can be easily crushed, and i guess porous too, were you gonna use it as your main substrate? keep in mind there about 1/4"-3/4" thick "rocks" and may have sharp edges.
-Scott.C


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## Rond (Jan 5, 2005)

I'll probably use the basalt in the bottom of my substrate layers and top the substrate with silica sand. The sand will eventually mix with other layers, but to me that is not important. I found this information in Wikipedia about basalt: “Basaltic cinders are often red, coloured by oxidised iron from weathered iron-rich minerals such as pyroxene.” Can the traces of Fe (Iron) in Volcanic Basalt be used by the plants? Does this mean that red cinders are richer in iron than black cinder?


If only the rare green sand and black sand could be available or very abundant, then I would definitely use that as my main substrate.


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## Brilliant (Apr 11, 2006)

http://www.snopes.com/luck/pele.asp
http://www.volcanogallery.com/lavarock2004.htm
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2001/05/17/MN135697.DTL

Uhh...I would rethink Hawaiian rock.


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## Rex Grigg (Dec 10, 2002)

But he lives in Hawaii so the curse doesn't apply. And since the product is bagged up if the curse does hit it will only affect those that actually removed the rock.

Rond,

Mixing substrates of two different sizes will only end up one way. The smaller size on the bottom and the larger size on top.


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## Brilliant (Apr 11, 2006)

Well I was just warning him, when he gets addicted or has a problem with the rock and discovers the company has burned to the ground he will have a problem. 

The curse applies to anyone, who do you think told me about it. Tourists are the only ones dumb enough to take it. Then they tell the story.

This is where I would insert my PICTURE of lava rock... from Waimea canyon to share.


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