New tank syndrome kills more fish than disease. It happens when you add fish to an uncycled tank and ammonia builds up to lethal levels. The solution is cycling your tank first — and with the right method, you can do it in 7 days.
What is the nitrogen cycle?
Fish produce ammonia through their waste and respiration. Beneficial bacteria (Nitrosomonas) convert ammonia into nitrite. A second bacteria (Nitrospira) converts nitrite into nitrate. Nitrate is relatively harmless and removed through water changes. This chain is the nitrogen cycle — and your tank needs all three stages to be safe.
The 7-day method: Seachem Stability
Seachem Stability is a bottled bacteria product that dramatically speeds up cycling. Day 1: Set up your tank, add dechlorinated water, run your filter. Add Stability at double dose. Day 2-7: Add Stability once per day at normal dose. Add a small pinch of fish food each day as an ammonia source. Test water daily. By day 7, ammonia and nitrite should read 0ppm — your tank is cycled.
Seachem Stability
Rapidly establishes the biological filter in freshwater and marine systems. The fastest way to cycle a new tank safely.
Signs your tank is cycled
Ammonia: 0ppm. Nitrite: 0ppm. Nitrate: 5-20ppm. Water is clear, not cloudy. At this point you can safely add your first fish — but go slowly. Add 1-2 fish at a time and wait 2 weeks between additions to let bacteria catch up with the new bio-load.
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