Let's talk Lava Rock.

[RogueAquarium]

I live in a place that is almost entirely COVERED with lava rock. The only places that are not are the fields farmers have spent generations slowly removing the lava rocks in order to be able to use it as a field. I have found several colors, consistencies ECT.

What would I need to do to make this abundant and free resource that people are LITTERALLY tossing into giant piles and trying to get rid of into a resource for my aquariums? 

Are only specific kinds of lava rock usable for aquariums?

What kind of sterilization could I do, considering the usual methods are unsafe with lava rocks? (boiling or oven heating can cause explosions of water trapped in the pours turning into steam)

 

[Fresh]

I'm using lava rock for the first time myself, seems like any lava rock is usable. I just rinse it out with warm water a whole bunch of times. I'm using it in my filter though, not sure if you mean that or for decor?

https://www.homedepot.com/p/Endless-Summer-7-lb-Lava-Rock-05002/100331664?MERCH=REC-_-searchViewed-_-NA-_-100331664-_-N

 

 

Edited July 16, 2021 by Fresh

[Kilrkitty08]

I seen an aquascape video where the guy put a bag of lava rock under his substrate to build a 'mountain' or high spot in the tank.  He also stated it would be a crazy amount of surface for bacteria to grow.  Is this true if he covered it with substrate?  I hope someone answers all of your questions @RogueAquarium

[HH Morant]

Lava rock is fine for aquariums. Gather it in a place that has not been sprayed with herbicides or insecticides, and wash it. It has more surface area than an ordinary rock, so that may give it an edge over other kinds of rock. It is relatively soft, so you can grind down sharp edges, if any, by rubbing rocks together or rubbing them against pavement..

[Tanked]

If you have access to free range lava rock, you should be trying to sell some of the better pieces.  I've been using LR harvested from my garden path for 6 months. I think it can be a good look.  It will never be completely clean so I get all of the nutrients included.  I had to by some bags of LR intended for the grill just to get some slightly larger pieces for a future hardscaping project.   I put the used rock in a shallow tray and let the sun and rain work on them for a few weeks. The store bought pieces were used straight from the package.

[Expectorating_Aubergine]

Just make sure it's not sharp. Lava rock can be EXTREMELY sharp!

[Patrick_G]

I used to live in central Washington and decorated my little 10 gallon tank with local Basalt I scavenged. It worked great and the fish thrived. I’m guessing from your handle that you in central OR so it’s probably the same general type of rock I used. 

[TheNanoAquariumGuy]

I have used mostly lava rock because it is cheap. My understanding is that red lava rock has higher iron content so it should help plants a bit on that end. However for aesthetics, I just use the black ones. The other major thing I was told (haven't experience it myself) but if you boil it, it could explode. So I used hot running water to clean it and to the tank it goes.

[PedroPete]

Lava rocks are great! I've scaped a few nano tanks with black lava rock - awesome for adding surface area for bacteria to grow and easy to use with java ferns and bolbitis to make nice scapes (IMO). Wash / rinse a bunch and/or soak them in a vinegar solution if you wanted to ensure they were clean. 

[Tanked]

On 7/20/2021 at 7:32 PM, TheNanoAquariumGuy said:

I have used mostly lava rock because it is cheap. My understanding is that red lava rock has higher iron content so it should help plants a bit on that end. However for aesthetics, I just use the black ones. The other major thing I was told (haven't experience it myself) but if you boil it, it could explode. So I used hot running water to clean it and to the tank it goes.

Some people just use a brush to clean their rocks, and some boil them.  Lava rock is so porous I would not be concerned about boiling. For most of us the boiling point of water is 212F.  Most if not all exploding rock stories arise from someone placing rocks in contact with the heat from a cooking/campfire.  Quickly superheating the rock in the fire 600-1000+F doesn't allow time for gasses to escape. 

[HH Morant]

On 7/21/2021 at 9:12 AM, Tanked said:

 For most of us the boiling point of water is 212F.  

OK, at first I thought this was an understatement and kind of funny. Then realized that the boiling point of water varies with altitude, so it is scrupulously accurate.

[TheNanoAquariumGuy]

On 7/21/2021 at 10:12 AM, Tanked said:

Some people just use a brush to clean their rocks, and some boil them.  Lava rock is so porous I would not be concerned about boiling. For most of us the boiling point of water is 212F.  Most if not all exploding rock stories arise from someone placing rocks in contact with the heat from a cooking/campfire.  Quickly superheating the rock in the fire 600-1000+F doesn't allow time for gasses to escape. 

Yea, again I have boiled it in the past and nothing happened, and later I was told of the risk so I just don't, because it does make sense if there is an expanding pocket if air it could happen. But chances are it would just crack and not explode if boiled. So I just been rinsing them with hot running water from the sink and I haven't seen a difference, but then again I bought mine from home Depot so it has probably been in a hot Warehouse and dry for a long time, if one is collecting from outside there is probably a higher risk. 

[MAC]

@RogueAquarium I collect and use lava rock as much as I can. The only thing I do is make sure I pull it from an area where it wouldn't have contacted any road run off or pollutants, rinse it of any debris and good to go. I would watch out and avoid pieces with extreme sharp edges. 

There's definitely plenty to choose out here in Oregon!

[DjNEOda1]

I use lava rock in my Hang on Back Filters for BB. Just make sure you CLEAN THE HECK out of it.

You might be better off just buying a bag because it is cheap and you never know what might be on random lava rock.

[Jungle Fan]

My tank has a whole layer of crushed lava rock underneath the top substrate for beneficial bacteria to colonize and help with flow of nutrients and  filtration, I've also previously used it in big filter material bags to help build up aquascapes towards the back of tanks, or to build elevated mounds for islands, or to support and stabilize driftwood, and as biological media in some of the trays of canister filters. After you crush it to desired size just make sure you rinse it really well, if you plan to use it on top of the substrate make sure it has no more extremely sharp edges, or that it is covered with glued on plants like moss, Anubias, Bucephalandra, or Java fern.  If it is covered with lichen before you crush it  I would soak it in hydrogen peroxide for two days repeatedly until the organic material is gone (over the period of two days the hydrogen peroxide turns into water), rinse it with plain water, and dry it in the sun. 

[RogueAquarium]

On 7/20/2021 at 4:53 PM, Patrick_G said:

I used to live in central Washington and decorated my little 10 gallon tank with local Basalt I scavenged. It worked great and the fish thrived. I’m guessing from your handle that you in central OR so it’s probably the same general type of rock I used. 

Good guess on name being inspired by the Rogue River, but alas no. I'm in a far more sad, brown, hot and desolate place, lol. The name is actually because I also own a business by that same name in a very different business sector and I just wanted to carry the name over.

I DID spend several years crawling all up and down that and other Oregon rivers though. Beautiful place. I'd take the Rogue over the Willamette any day of the week.

[Chris turtlerouge]

Im just curious, cant the campfire rocks thats been in that fire be used also?

[Tanked]

On 12/27/2023 at 1:42 AM, Chris turtlerouge said:

Im just curious, cant the campfire rocks thats been in that fire be used also?

That's a good question.

Are you thinking about a real wood burning campfire, or the backyard gas powered fire pit?   I'm not a chemist, so my best guess is that while the rocks are inert, campfire residue would wreak havoc on the water chemistry.

 

 

[Chris turtlerouge]

On 12/27/2023 at 11:15 AM, Tanked said:

That's a good question.

Are you thinking about a real wood burning campfire, or the backyard gas powered fire pit?   I'm not a chemist, so my best guess is that while the rocks are inert, campfire residue would wreak havoc on the water chemistry.

 

 

Ok, thank you

[PotatoFish]

Lava rock is good stuff!

I have heard of using rock to "build up" the bottom of an aquarium, but I am thinking it's a lot of weight. Serpa Design suggested using the plastic grid thing (picture from Google search below) to help distribute the weight of large pieces of hardscape.

on burying lava rock
However, I was thinking, if the rock is just going to be buried by gravel, why not just use that expanding aquarium foam and cut it down? Cory had mentioned in one of his videos, please do correct me if I misremember, that the beneficial bacteria only live a few inches down from the surface, so if you have a ramp that is far higher than that, the extra surface area from the buried lava rock might not be as effective.

[Chris turtlerouge]

Just a thought:

Wouldn't that be like using leggo  blocks? 

MD on one of his videos used larger lava rocks to build up, he kept his foundation around 2-3" but used larger rocks to build up and he hid some of that behind plants.