计算无鱼开缸时需要添加多少氨水才能达到目标ppm，支持任意氨水浓度。
Fishless cycling establishes beneficial bacteria (Nitrosomonas and Nitrobacter) in your filter before adding fish. You dose ammonia to feed the bacteria, who convert it to nitrite, then to nitrate. The cycle is complete when ammonia and nitrite both drop to 0 in 24 hours.
Most fishless cycling guides recommend starting at 2–4 ppm ammonia. 2 ppm is a good starting point for most tanks. Avoid going above 4–5 ppm, as very high ammonia can actually inhibit bacterial growth.
Use pure ammonia with no surfactants or additives — the bottle should list only ammonium hydroxide (NH4OH) and water. Common concentrations are 9–10% and 25–29%. Check the label and enter the percentage into this calculator.
The cycle is complete when: ammonia drops from 2 ppm to 0 within 24 hours, and nitrite also drops to 0 within 24 hours. Test daily. A complete cycle typically takes 4–8 weeks with pure ammonia, less with a bacterial starter.
Dose ammonia every 1–2 days to keep levels at 1–2 ppm once bacteria establish. Let levels drop to 0 before re-dosing to mimic a fish load. Do a large water change (80%) before adding fish to flush accumulated nitrate.