Lava rocks as the FW version of Live Rock?

[Luananeko]

Has anyone heard of using lava rocks in FW tanks to keep nitrates low, similar to how SW uses live rock? Is this a legitimate thing, or just a sales pitch? Using Lava Rocks to Denitrify Aquariums, Fish Bowls, and Ponds.

I'd imagine having lava rock in the tank would be asking for fish injuries... But I guess if the benefits are real you could put them in a sump. Obviously regular water changes are the ideal way to keep nitrates down, but I'm curious if this has any merit as an alternative to understocking or doing multiple water changes a week for the health of super nitrate-sensitive invertebrates & fish. What do you guys think?

 

[TheCommunityCichlid]

I keep lots of lava rock in my tanks, have little to no injuries but I haven't really noticed any "special" abilities but it defiantly can host a lot of bacteria in it so I could see the benefits. Some filters even use it as a media. Good thing I have over 200 pounds of denitrifying rocks lol

 

[Luananeko]

Those do look really nice! I guess I'm just paranoid about injuries because I tend to keep long finned fish or fish with sensitive parts (bettas, guppies, long-fin GBRs, long-fin danios, gourami, loaches, etc). I learned really quickly to make sure all my decorations in my betta tanks were smooth to avoid tearing up their gorgeous fins...

 

[TheCommunityCichlid]

Those do look really nice! I guess I'm just paranoid about injuries because I tend to keep long finned fish or fish with sensitive parts (bettas, guppies, long-fin GBRs, long-fin danios, gourami, loaches, etc). I learned really quickly to make sure all my decorations in my betta tanks were smooth to avoid tearing up their gorgeous fins...

I keep mine in a African Cichlid they enjoy the caves that are easily formed by the rock. I've got some long fin gold rams but I don't keep lava rock in there since they will have a hard time spawning on it.