Free tank cycling timeline calculator. Enter tank type + bacteria source, get the estimated days to complete cycle. Plan your stocking date with confidence.
Cycling speed depends on bacterial seeding source + temperature + ammonia source. Live rock from a mature tank is the fastest seed (sometimes 1-3 days "instant cycle"). Bottled bacteria (Dr. Tim\'s, Bio-Spira, Stability) speeds the cycle to 7-14 days.
Cycle complete signal: dose ammonia to 2 ppm; if it converts to 0 ammonia + 0 nitrite within 24 hours (with nitrate present), the cycle is complete. Do a 50% water change before adding fish.
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