About 10kgs rock seeded from tank over 2 years old.
There's about 12kg of unseeded rock in there.
And planning on moving remainder of live rock from other tank over next few weeks.
Sugar cube sized lumps, I have really been hammering it to try and get some readings and nothing.
To my mind, it's probably cycled. I, personally, would still want to see a Nitrate reading to sleep better at night, but that's basically the end-game. If you read nitrate with zero ammonia and zero nitrite, you're "cycled" IMHO.
How "cycled" is another matter that we don't often discuss on here. I know you understand,
Rabidwolf. Just for the sake of the larger discussion... that doesn't mean that the tank is ready to be fully stocked with nine fish. It means there's enough ammonia processing material in it to process a certain amount.
I think that's why the discussion @
brandon429 and @
EMeyer are having is so fascinating. To Brandon's point, yeah, sure.. visual observation is how we do most things. It's how Newton discovered gravity. If I go to the Dr. with a puss-filled wound, the doc gives me an antibiotic. They can tell it's bacteria bc of the visual cues and signs. There is no need to run a lab test on a piece of my tissue to confirm it.
On the other hand, "how cycled?" The doc can't tell how much bacteria is in the wound. Perhaps some seriously experienced hobbyists can look at a piece of rock, feel its weight, see its porosity, and give a good "gut" judgment on how much livestock and feeding it can support. I can not. I'd bet brandon probably can

. Can anyone who reads an explanation?
To my mind, that's where Emeyer's preference for testing comes into play. It's not so much to prove that the rocks can cycle ammonia, but to what extent? If I put a well cycled, coraline-encrusted, crawling w tube worms rock in a 40breeder, but the rock is only the size of a golf ball, can I call that tank "cycled?" It will process ammonia into Nitrate, no doubt. Will it process enough? If I dose a set level of ammonia and time the process, it can be gauged. Ofc, if the rock is the size of a bowling ball, even a noob like me could safely call it "cycled"... at least enough for a small fish or two.