Question 1

How long does it take to cycle a saltwater tank?

Accepted Answer

Usually two to six weeks, but it varies a lot with how you start it. Cured live rock and a bottled-bacteria dose can shorten it; dry rock started from scratch takes longer. The clock does not matter as much as the test result: you are cycled when the tank turns a ~2 ppm ammonia dose into 0 ammonia and 0 nitrite within 24 hours.

Question 2

How do I cycle a reef tank without fish?

Accepted Answer

Fishless is the recommended way. Add an ammonia source (a bottle of pure ammonia, or the die-off from uncured live rock) so the bacteria have food, dose a bottled nitrifying-bacteria starter if you like, and test every few days. Never cycle with fish as the ammonia source - it is stressful and often fatal, and it is unnecessary.

Question 3

When can I add fish and coral after cycling?

Accepted Answer

Once ammonia and nitrite both read 0 and nitrate is present, do a large water change to bring the nitrate down, then add your cleanup crew and a single hardy fish first - a few at a time, never all at once. Corals come later, after the tank has matured and parameters are stable. This tracker flags the completion test and the water-change step.

Question 4

Where is my cycling log stored?

Accepted Answer

Only in your own browser (via localStorage). Nothing is uploaded, there is no account, and we never see your readings. The trade-off is that the log lives on this device and browser - clearing your browser data will erase it.

Cycling tracker

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