Is there a Coral/Motile Invert Safe Black Sand? CaribbSea Hawaiian, Yes Or No?

[Fish Fan]

Hey all! I'm posting this question here in the Chem section to get hopefully some real science and more than just anecdotal observation. RHF, please feel free to move this to the Aquascaping section or wherever it's more appropriate if needed

I have always liked the look of black sand, and I purchased 4 bags of the CaribbSea Hawaiian Black sand somewhere around 2015, maybe 2017. I learned after I bought it that it get's a bad rap for a couple of reasons, so these bags have been sitting in my garage all these years.

Currently, I'm setting up a 25 gallon coral/motile invert QT tank where new arrivals will be homed for 45 days or so, before going into my display tank. This tank will "live" in the same room as my DT which will have live sand and rock from Tampa Bay Saltwater. I want my 25 to be visually different from my main DT. I have been planning on bare bottom, but when I look into the tank (no water yet, just building the system), I can see the black foam mat on the underside, and it's kind of grayish and splotchy, and doesn't look great. I had ordered, but was then talked out of, using a piece of HDPE on the bottom.

I started to think about the Hawaiian Black sand again, and the two big things I had always heard is that it's magnetic, and that it has some smaller particles that can blow around; two things I think I can overcome (detailed bellow).

But just tonight I looked again, and now at least some people are claiming this sand contains metals (I saw nickle and vanadium mentioned, and possibly copper as well). Some people claimed this was confirmed via ICP testing, which seems compelling, yet others said they've used this sand for years without trouble. Some mentioned that only certain lots of this sand were affected, yet others argued that any black sand was going to be volcanic and contain metals.

What gives here? This product has been on the market a very long time (the CaribbSea Hawaiian Black specifically). Does it really contain metals that would be deleterious to corals or any motile inverts?

My plan for the CaribbSea Hawaiian that I have on hand was to dry and then sift the sand, and use just the largest particles, thereby removing the "fines" that may blow around. And as far as being magnetic, yes I admit my pump impellers may suffer, but I don't care that much about a magnet scraper as I generally tend to prefer the "blade on a stick" type scraper anyway.

Please keep in mind, this is specifically for a coral/motile invert QT tank, this will never have fish, so no worries over Gobies or Wrasses, etc.

If not the CaribbSea product, is there another sand on the market that I could use here? Even if it's not jet black, just something "different" from the beige/white "typical" sands?

Thanks in advance for the help!

 

[ieatbugman]

I’ve always loved this sand, but never tried it. I have seen a black rocky substrate at my local lfs, and all of there stuff is very happy(sorry i know this is anecdotal). So presumably its either the Hawaiian black sand or some other substrate, i will ask next time im there

 

[Fish Fan]

I’ve always loved this sand, but never tried it. I have seen a black rocky substrate at my local lfs, and all of there stuff is very happy(sorry i know this is anecdotal). So presumably its either the Hawaiian black sand or some other substrate, i will ask next time im there

Thank you for your reply! If it's black and chunky, it may be black lava rock, which was popular a very long time ago (like the 1980's, I believe (because I was around then lol!)). And, that would definitely be a similar, *volcanic* rock.

Is this a fish only tank, or do they also have corals and other inverts?

 

[Fish Fan]

Bump! Anyone have any insight to this sand or another black sand, or even just a "different" sand? I'd really appreciate it!

 

[DanConnor]

I think Seachem Gray Coast sand is chemically benign. I just set up a 60 gallon cube with it. It is not real black but pretty close. You really need to rinse it though- its mixed with a superfine silt that is lighter in color and will settle on top of the sand if you just dump it in. Once rinsed, the color is quite nice.

 

[jermzisurmom]

I have the black chuncky stuff from Hawaii I enjoy it very much I have fish and inverts yes it will scratch ur glass but so will most stuff, yes it is magnetic and not worried about metals I have a rusty hose clamp in my water in the sump... hope this helps!

if u like it go for it.

 

[Fish Fan]

I think Seachem Gray Coast sand is chemically benign. I just set up a 60 gallon cube with it. It is not real black but pretty close. You really need to rinse it though- its mixed with a superfine silt that is lighter in color and will settle on top of the sand if you just dump it in. Once rinsed, the color is quite nice.

Thank you from out near Canandaigua area

 

[Fish Fan]

I have the black chuncky stuff from Hawaii I enjoy it very much I have fish and inverts yes it will scratch ur glass but so will most stuff, yes it is magnetic and not worried about metals I have a rusty hose clamp in my water in the sump... hope this helps!

if u like it go for it.

Awesome pics, thanks for sharing! I saw where many people were complaining that their tanks were languishing and then ICP testing reveal super high this or that. Yet MANY people have reported that this sand is fine.

I think my idea to dry and then sift it for the largest particles is solid.

Anyone else have experience or knowledge here? Thanks for you help in advance!

 

[Reefer Matt]

I have used that sand in my sps tank. It is lava “sand” and has iron in it. It will scratch the glass if a magnetic cleaner is used. Other than that, no issues with livestock or chemistry. I ended up removing it after five years to go bare bottom.

 

[Fish Fan]

I have used that sand in my sps tank. It is lava “sand” and has iron in it. It will scratch the glass if a magnetic cleaner is used. Other than that, no issues with livestock or chemistry. I ended up removing it after five years to go bare bottom.

Thanks for your reply!

I understand it's magnetic, I'm not worried that because I prefer a "razor on a stick" to a magnetic scraper anyway.

Can I include you in the camp of "I've used it, and the stories of heavy metals are largely overrated"? Is it possible that those users were experiencing something other than a reaction to this sand?

Thank you so much for your help!

 

[Randy Holmes-Farley]

I don’t know the answer to this question. I’d give a few comments.

1. Natural beach sand would be much less likely to be a problem than ground up lava since it has had a long time to have exposed metals on the sand surfaces to be washed away. It is also much more rounded.

2. Unnatural sands from ground rocks may vary greatly in risk depending on the exact composition of the rocks.

3. The worst effects will be with new sand. After some period of time, most of the concerning metals will have washed away.


Some articles that study natural black beaches:

https://www.sciencedirect.com/science/article/abs/pii/S0273230017303963

Elemental Analysis and Radionuclides Monitoring of Beach Black Sand at North of Nile Delta, Egypt - Pure and Applied Geophysics

A study was carried out on the concentrations of elements presented in beach black sand samples collected from North of Nile Delta along Mediterranean Coast using instrumental neutron activation analysis (INAA) as an effective analysis technique, especially for monitoring elements. The Egyptian...

link.springer.com

. Therefore, the black sands from North of Nile Delta are not recommended for use in building constructions due to high radioactive doses.

 

[Fish Fan]

I don’t know the answer to this question. I’d give a few comments.

1. Natural beach sand would be much less likely to be a problem than ground up lava since it has had a long time to have exposed metals on the sand surfaces to be washed away. It is also much more rounded.

2. Unnatural sands from ground rocks may vary greatly in risk depending on the exact composition of the rocks.

3. The worst effects will be with new sand. After some period of time, most of the concerning metals will have washed away.


Some articles that study natural black beaches:

https://www.sciencedirect.com/science/article/abs/pii/S0273230017303963

Elemental Analysis and Radionuclides Monitoring of Beach Black Sand at North of Nile Delta, Egypt - Pure and Applied Geophysics

A study was carried out on the concentrations of elements presented in beach black sand samples collected from North of Nile Delta along Mediterranean Coast using instrumental neutron activation analysis (INAA) as an effective analysis technique, especially for monitoring elements. The Egyptian...

link.springer.com

. Therefore, the black sands from North of Nile Delta are not recommended for use in building constructions due to high radioactive doses.

Thanks for your help here! I'll take a look at the link, but aside from this CaribbSea sand, is there any other non-white/beige sand that you know to be completely reef safe? Thanks again!

 

[Randy Holmes-Farley]

Thanks for your help here! I'll take a look at the link, but aside from this CaribbSea sand, is there any other non-white/beige sand that you know to be completely reef safe? Thanks again!

I don’t know much about the suitability of different black sand products except a fair number of folks who liked the initial look either stopped using it or are not happy with it as time goes by. I do not recall the exact reasons.

 

[Fish Fan]

I don’t know much about the suitability of different black sand products except a fair number of folks who liked the initial look either stopped using it or are not happy with it as time goes by. I do not recall the exact reasons.

Thank you for your reply!

 

[Reefer Matt]

Thanks for your reply!

I understand it's magnetic, I'm not worried that because I prefer a "razor on a stick" to a magnetic scraper anyway.

Can I include you in the camp of "I've used it, and the stories of heavy metals are largely overrated"? Is it possible that those users were experiencing something other than a reaction to this sand?

Thank you so much for your help!

I don’t know if other’s account of using the sand are true or not, and can only speak of my experience. The sand I used is a natural product, and not artificially crushed up lava rock. My experience with black sand is well documented on my channel if anyone wishes to look.

For more info, look up,
Punalu'u Black Sand Beach

 

[Randy Holmes-Farley]

There are lots of comments from users pro and con on reef2reef, which makes me very concerned.
Here’s a typical negative result:

I had the same experience as you. ICP tests before and after removing the black sand confirmed it was the culprit for the metals. Besides coral troubles I couldn’t keep any crabs or urchins alive for long either. Once I swapped the sand though everything immediately started improving.

CaribSea Hawaiian Black Sand Can Poison Your Tank

So I've seen a couple posts about this, but I felt the need to share my experience with this sand and my strong opinion towards it. I waited about 3/4 weeks to verify if the actual problem stemmed from the sand or something else. I did no other changes with my tank in terms of flow, filtration...

www.reef2reef.com