qustion about my cycle

[Madmak]

The cycle is all about populating the different forms of bacteria. When you add live rock, live sand, or old water to the equation it can change everything.

What's important is the balance. Life or death creates ammonia, nitrifying bacteria consume ammonia but create nitrites, denitrifying bacteria consume nitrites but create nitrates and phosphorous. We export these with our filters, algae, water changes, etc.

A spike in any of these chemicals means the balance is off and time is needed for bacteria to stabilize their population. A spike can happen at any time, not just at start up. An obvious cycle is almost always guaranteed at start up but will happen any time the balance is upset. Try adding 10 fish all at once, or leaving a dead animal or 2 in the tank.

A mature and seasoned tank has enormous amounts of bacteria and micro fauna that helps keep it stable through almost any situation. That's what we are all shooting for I think??

That's my take on things in layman terms anyhow. It's a much more complex formula than that if you want it to be.