Is lava rock reef-safe?

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Hello, I was wondering if black lava rock was reef-safe. It is this specific brand, most sources say it is fine forfreshwater but nothing about marine tanks. Thank you
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I haven't tried this long term but I can think of a couple things to consider. The main risk is that they'll leach some kind of harmful mineral/metal but I really doubt that'll be an issue in saltwater since it's never been one in freshwater. I often see people keep Sulawesi shrimps with all lava rock aquascapes and it's been said that they're more sensitive than Acropora. It does leach some elements and that's something I and many other hobbyists take advantage of to help freshwater plant growth. I've seen videos on youtube about someone who does the same with macroalgae and never has to dose micronutrients in his lava rock tank. It'll probably be beneficial if you use it IMO. Hawai'i is made of volcanic rock after all...
 
I haven't tried this long term but I can think of a couple things to consider. The main risk is that they'll leach some kind of harmful mineral/metal but I really doubt that'll be an issue in saltwater since it's never been one in freshwater. I often see people keep Sulawesi shrimps with all lava rock aquascapes and it's been said that they're more sensitive than Acropora. It does leach some elements and that's something I and many other hobbyists take advantage of to help freshwater plant growth. I've seen videos on youtube about someone who does the same with macroalgae and never has to dose micronutrients in his lava rock tank. It'll probably be beneficial if you use it IMO. Hawai'i is made of volcanic rock after all...
oh ok thx for letting me know. im still not sure i found some video from 10 years ago talking about how it leeched silicates and caused a bunch of algae, idk tbh
 
Hello, I was wondering if black lava rock was reef-safe. It is this specific brand, most sources say it is fine forfreshwater but nothing about marine tanks. Thank you
1769828790833.png


It will likely leech. Good, bad and indifferent. I also saw a Lowes employee spraying their rock with insecticide one time. You really just have no chain of control and don't know what's going to be released from it.

Why would you risk it? There are lower risk alternatives. If its about saving a few dollars...I advise against it.
 
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It will likely leech. Good, bad and indifferent. I also saw a Lowes employee spraying their rock with insecticide one time. You really just have no chain of control and don't know what's going to be released from it.

Why would you risk it? There are insert / lower risk alternatives. If its about saving a few dollars...I advise against it.
i needed something like texas holey rock thx for letting me know though. i'll stay away from it
 
i needed something like texas holey rock thx for letting me know though. i'll stay away from it

Department store lava rock shares zero qualities with texas holey rock. It is very porous but otherwise just pieces of solid rock. Typically no character. Its inert vs texas holey rock being a PF buffer. Doesn't look or act the same at all.

Its a great filter rock though. Also good at exfoliating your hands...aggressively. If you have ever worked with large quantities of it you will know what I mean.

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Didn’t realize this thread existed . I put some large pieces or red lava rock in a 10gal with a sponge filter , peppermint shrimp , lantern basslets , ghost shrimp and yellow ball sponge and some clams, nothing died . My caulerpa did grow in it . So I put some small rocks in my sump of the 125 . The jury is still out . I just purchased some urchins . I think they are like canaries in a coal mine . I haven’t added them yet because they are in QT . I had starfish and urchins die after adding the Ceramic marine pure . I attribute their death to the complete breakdown of the marine pure . Hi aluminum. I didn’t test it with an ICP . So I use anecdotal evidence .
 
Didn’t realize this thread existed . I put some large pieces or red lava rock in a 10gal with a sponge filter , peppermint shrimp , lantern basslets , ghost shrimp and yellow ball sponge and some clams, nothing died . My caulerpa did grow in it . So I put some small rocks in my sump of the 125 . The jury is still out . I just purchased some urchins . I think they are like canaries in a coal mine . I haven’t added them yet because they are in QT . I had starfish and urchins die after adding the Ceramic marine pure . I attribute their death to the complete breakdown of the marine pure . Hi aluminum. I didn’t test it with an ICP . So I use anecdotal evidence .
Any update? Thinking of using some cured lava rock for copepods
 
I would not put lava rock in my tank. Too much chance of heavy metal release from it.
 
FW aquarists have been using lava rocks for years - both as filter media and aquascapes. Though, I wouldn't use lava rock from some big box store. Instead I would get it from a known aquarium vendor.
 
I used black garden lava rock in a nano many years ago as an inexpensive "base" rock. It did not cause any issues, as far as I know. The rock had been outdoors for who knows how long, and was soaked in salt water for a while before I added it to the setup.

The advantages: Porous. Light weight. Extremely cheap. Kinda nice to look at, created a striking contrast to fluorescent corals, and basically vanishes under blues. Very easy to glue due to the mechanical bond.

The disadvantages: It was a detritus trap unless I aggressively attacked it with a turkey baster. Porosity means that if any sort of pest gets a foothold it's there forever. Sharp and abrasive. The red kind will be very high in iron. Doesn't really keep the striking look long-term as it gets covered in coralline.

I did eventually phase most of the lava rock out when I needed more room for coral, but I think it kept a few chunks until the very end.

Any update? Thinking of using some cured lava rock for copepods

It is basically a pod (and mini-duster) factory, IMO. If you're doing a separate culture setup it should work well for that. I never had issues, but I did soak it for a while first. I'd probably do a basic copper check on the "curing" bucket just in case.
 
FW aquarists have been using lava rocks for years - both as filter media and aquascapes. Though, I wouldn't use lava rock from some big box store. Instead I would get it from a known aquarium vendor.

And those aquarists do not have the trace metal concerns reefs do. Even black sand has been shown to release elements.
 
Actually they do. You think cyano and various nuisance algae are limited to the Reefing application?

No, and pests are not the concern, IMO. It is the high toxicity of certain trace elements to invertebrates and corals that concern me, and have been found with black sand.
 
No, and pests are not the concern, IMO. It is the high toxicity of certain trace elements to invertebrates and corals that concern me, and have been found with black sand.
Well,

Maybe you should include the "IMO" with respect to black sand considering many vendors sell it specifically for reefing applications.

Additionally, companies like ADA make some of the finest substrates in the world using volcanic rock and volcanic ash.

And isn't zeolite made from volcanic rock and ash too?

My only suggestion to the OP was to not use some rock from some gardening center from some big box store. No telling whats in that stuff 🤨
 
Maybe you should include the "IMO" with respect to black sand considering many vendors sell it specifically for reefing applications.
In no way does that mean it's safe to use. I have four bags of Caribbsea Hawaiian Black in my garage that I bought like 15 years ago, and never used after learning of the problems many people had with this sand. While some repot it's alright to use, many reefers have had problems with this sand, which you can see in the thread Randy linked above.
 
In no way does that mean it's safe to use. I have four bags of Caribbsea Hawaiian Black in my garage that I bought like 15 years ago, and never used after learning of the problems many people had with this sand. While some repot it's alright to use, many reefers have had problems with this sand, which you can see in the thread Randy linked above.
I don't have any interest in black sand. But like everything else in this hobby YMMV. Period.

One example: How many bad batches of salt did TM salt make years ago; was that safe? And yet "bazillions" of people use TM salt to this very day.

There's this culture of absolutes in these forums, that are a bit annoying to say the least...
 
Well,

Maybe you should include the "IMO" with respect to black sand considering many vendors sell it specifically for reefing applications.

Additionally, companies like ADA make some of the finest substrates in the world using volcanic rock and volcanic ash.

And isn't zeolite made from volcanic rock and ash too?

My only suggestion to the OP was to not use some rock from some gardening center from some big box store. No telling whats in that stuff 🤨

Yes, it is my opinion, as I VERY CLEARLY INDICATED.

I would not put lava rock in my tank. Too much chance of heavy metal release from it.

Obviously that is an opinion stating what I personally would do, and why.


Bad experiences have also been the experience of some folks that they recounted here: that black sand leads to a variety of problems. Sometimes it may be OK, and others it is not. Check the link I posted. That person had an issue.

No, zeolites are a different chemical than lava rock. I'm not a fan of zeolites either, but for entirely different reasons.
 
Yes, it is my opinion, as I VERY CLEARLY INDICATED.

I would not put lava rock in my tank. Too much chance of heavy metal release from it.

Obviously that is an opinion stating what I personally would do, and why.


Bad experiences have also been the experience of some folks that they recounted here: that black sand leads to a variety of problems. Sometimes it may be OK, and others it is not. Check the link I posted. That person had an issue.

No, zeolites are a different chemical than lava rock. I'm not a fan of zeolites either, but for entirely different reasons.
Maybe you should reach out to all the fresh water enthusiasts who have nothing, but lava rock as their hardscape material while keeping very sensitive freshwater shrimp (e.g., caridina).

Not trying to be the grammar **** or anything but no, your opinion wasn't "clearly" articulated.
 

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