Tanks were cleaned on a daily basis. Water quality parameters were measured daily and maintained within acceptable limits for the duration of the experiment, these were: pH 7.8–8.4, salinity 30–34‰, dissolved oxygen 6–7 mg/L, ammonia 0.0–0.1 mg/L and nitrite 0.0–0.01 mg/L. Half-hourly logged temperatures within the broodstock chambers were within ± 0.2 °C of the prescribed treatment temperatures.
Diet for the broodstock in the breeding tanks consisted of pipis (Plebidonax deltoids), green mussels (Perna canaliculus) and squid (Loligo sp.) provided once per day after 3 pm at around 3% bodyweight adjusted according to observation. Feed rate remained consistent between tanks, and was monitored daily. Once berried females were moved into the egg incubation system, feeding consisted of one green mussel every second day to minimise fouling and to mitigate any negative effects such as the dropping of the egg mass which can be caused by bacterial and fungal infection of the egg mass under high organic load (MacDairmid and Sainte-Marie, 2006).