Lava rocks for media filter??

Following as I’ve been wondering the same. They have a lot of holes and by theory they would be great in a sump. I’ve just never heard of anyone doing it and haven’t found anything on them being used. I would think it would leach Iron, sulfur, and phosphorus but I honestly don’t know. Maybe @Randy Holmes-Farley could help with this one. What’s your thoughts doc?
 
Last edited:
Why not just go with pond matrix or one of those media things get a gallon for like 15$
 
It depends. Some lava rock has harsh metals in it while some might be fine.

Lace rock or pure limestone will work just as well, but can have bound terrestrial phosphate.
 
Yah. Some heavy metals and can have pH issues. I'd stay away from it although having said that I do recall a mixed FW tank I had 50 years ago that went on forever. Still, SW is a different animal, so I'd say no.
 
you have to get the right type of lava rock ,, it needs to be 100% volcanic , and not that other crap ,, I have it in my canister instead of biomax and bioballs, and in my 2 hob marineland 50g rated filters aslong as your first media tray has a coarse sponge the second can be lava rock then third , seachem or activated carbon(start with small doses of carbon if just starting to use in DT) at 7.99 a bag 15lbs at Canadian tire its the cheapest alternative to live rock(Which is on average 6.99- 9.99 per lbs in Canada) and that's not even pukani or fiji lol its mostly base rock and diy quickcrete rocks that has been in a sump or developing tank for years
 

IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

  • Yes!

    Votes: 32 45.7%
  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%
  • No.

    Votes: 26 37.1%
  • Other (please explain).

    Votes: 3 4.3%
Back
Top