How do you tell when live rock has fully matured?
 

Hi all.

I can see the rocks in my tank changing bit by bit every day, but at what point are they considered 'live'? what does a fully mature FOWLR tank look like?

Thanks,

Cured when your tests show no ammonia or NO2 present.

I don't usually have those now (though occassionally there are trace amounts). I am, however, running a sump and a Fluval cannister filter, and I change water every week. It seems to me there are lots of factors that contribute to NH3 and NO2 levels.

So I guess my question is, will all rocks completely change? How heavy does the growth get?

Do you mean you started with dead, dry rock, rather than 'live rock'? If your tank is mature, you will know because there will never be ammonia, on a normal day... ammonia signals something is wrong.