Will "Fragzone" rubble leech phosphates?

[SamMule]

I have a stable running 16g biocube that is starting to grow some nice coralline and a RSM250 coming soon. Bought a bag of Caribsea "Fragzone" rubble and would like to start "seeding" it with good bacteria and coralline by piling it in the bottom of my cube while I wait for the new tank. Might also make a nice pod haven too!

If I do this, am I risking a phosphate spike in the little tank with new rock? Or does the phosphate leeching only come from previously used rock?

 

[Flippers4pups]

I have a stable running 16g biocube that is starting to grow some nice coralline and a RSM250 coming soon. Bought a bag of Caribsea "Fragzone" rubble and would like to start "seeding" it with good bacteria and coralline by piling it in the bottom of my cube while I wait for the new tank. Might also make a nice pod haven too!

If I do this, am I risking a phosphate spike in the little tank with new rock? Or does the phosphate leeching only come from previously used rock?

Good question. Caribsea says it's coated with calcium carbonate and is colored. I believe its rock taken from the ocean, but don't quote me on that. Chances are it shouldn't raise P04, but "curing" in a tub of saltwater with bacteria would reveal, with testing, 100% if it will.

Most dry rock is "mined" from the ground very close to the shoreline. It's cleaned by power washing and left out in the sun to dry. This rock can hold Phosphate and could leach it back into water until equilibrium happens. Which can be a long time.