# Onyx Sand



## Phtstrat (Sep 15, 2004)

Hey all, I work at PetSmart and saw a bag of black sandy looking substrate with the gravel. It was made by Seachem I believe (I already threw the bag out), and was called Onyx Sand, which according to this bag was a great planting substrate.

I got a 15.6 pound bag (odd size right?) of it and dumped it into a tank full of water. Considering that it cost about $20.00 for that bag I wanted to waste as least as I could. Right now it is settling and I'm running some of my heavy duty filters on it to aid in the process.

My question is: Has anyone tried this stuff? Does it look good when settled? Is it actually a good substrate for plants? Right now it looks really weird on the bottom of the tank why?

Thanks in advance for any replies.


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## shoe997bed263 (Oct 15, 2004)

is it the stuff that looks like coarse grained pepper? if it is i had it in my cichlid tank but it was making my water alittle brown. did not like it so i took it out. sorry if this is not the same stuff


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## spree_rider (Mar 20, 2004)

from what i have heard from other forums and mailing lists, its second best stuff for growing plants, best being flourite,, i would love to use it on a tank.


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## Gumby (Aug 13, 2004)

It looks great in planted tanks. We use it in a few tanks at work. Like someone said, the only thing better for plants is flourite. And one problem you may have is that Onyx is known for buffering up the pH and hardness. Some South Amercian and Asian plants my not like that too much. Check your water parameters in about a month and see how things are going.


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## Phtstrat (Sep 15, 2004)

Thanks for the replies guys. Very good information.

The sand has finally settled, and there was a fine gray powder on it. I plan on stirring that stuff off after school today. I did a part this morning and it is looking real nice.

As for the quality in comparison to flourite, we didn't have any flourite besides an ugly dark red color, and I liked the black sand look.


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## Scolopendra (Feb 24, 2005)

I use the flourite with black sand ontop.....works well and has great contrast. AS for the onyx...It seems to work fine as ive never had any returns or complaints.


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## Raul-7 (Sep 1, 2004)

Phtstrat said:


> Thanks for the replies guys. Very good information.
> 
> The sand has finally settled, and there was a fine gray powder on it. I plan on stirring that stuff off after school today. I did a part this morning and it is looking real nice.
> 
> ...


But beware Onyx Sand will raise your kH levels, it leeches out Mg and Ca readily. The more acidic the water, the more it will leech out.


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## hughie (Sep 7, 2003)

Just today i asked in my lfs how much the bag of Onyx sand was, i was told "its alot, about £22.99 per bag, we used some and by the time we had washed it, we lost a quarter of the bag down the plughole. Better off with flourite gravel".

So as you might tell i didnt buy it, good sales pitch dont you think? He should be up for salesman of the year!


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