Mildew inside lava rock?

[musicman]

I think that's the general suggestion. I am going to pour boiling water over it. I'll do this to initially kill remaining organics, then I am going to cycle the rock in a 5 gal bucket.

I would just cycle it, but I don't know what could still be in the rock. I'd rather play it safe and kill existing bacteria (or worse) before colonizing some of my own.

[musicman]

The cycling is in progress. Ive got about 2ppm NH4 and 1 ppm NO2.
Off to a good start.

What happens when there are no more organics to decompose?