The efficacy of the aquatic anaesthetic AQUI-S® for anaesthesia of a small freshwater fish, Melanotaenia australis
For stage four anaesthesia of the western rainbowfish Melanotaenia australis the most efficacious concentration of AQUI-S® was found to be 80 mg l−1 when five different doses were tested at 27° C (range 26·5–27·5° C). This gave a mean ±s.e.(n = 10) induction time of 140·4 ± 8·9 s and recovery time of 180·2 ± 8·9 s and resulted in 10% mortality when fish were continuously exposed for 15 min. All fish given this dose during induction and recovery time trials ate within 1 h of recovery, and there was zero mortality during a subsequent 1 month monitoring period.