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Black Sand


Apr 29, 2021
I am interested in designing my tank to resemble a hydrothermal vent with black sand (Caribsea Hawaiian Black) but I have a couple worries.

People have compained about it being magnetic. My tank is acrylic and I am kind of obsessed about keeping it scratch free.

Also, some people have posted it may have heavy metals (though no one is certain, just based on theorizing between the magnetism and poor coral health).

I'd strongly prefer this black sand but I have a feeling I'll have to use the standard Fiji Pink.
My first tank had black sand and after years of being setup, when I took it apart I found rust deep in the sand bed and on the bottom glass. No clue what this means or if its safe or not.
I don’t have a clue about the chemical composition of black sand- but if it’s left rust in other tanks, that sounds like bad news!
Yeah, any type of metal in your octopus tank is a huge no-no, especially copper in any form. Sticking with tried and true methods sounds best to me!
Ended up going with Ocean Direct sand - if I can't have black at least I have every size of grain.

I love the look of the oolite but I've read its a huge pain and I am extremely obsessive about keeping my acrylic scratch free

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