After being harvested, fry are graded according to size. Before packing, the fry is conditioned for 24 h in plastic pails floating in a concrete tank. This procedure is necessary to allow the fish to empty their stomach, and as a part of sanitary control to prevent transporting any fish disease that might be carried with the fry. The latter is treated with 5 ppm of acriflavine solution or 0.5 ppm of copper sulphate solution for 5–10 minutes. During the conditioning period, the fry will be abstained from feeding.
The seabass fry can be transported in airtight carriers with oxygen. A commonly used container is a plastic polyethylene bag. The standard size of the polyethylene used for this purpose is 40 × 60 cm. The animals are packed in double plastic bags with 6–7 1 of water. The plastic bags are then inflated with oxygen. The oxygen level is measured by collapsing the bag to water level then placing hand down 10 inches from top and filling with oxygen until there is a feel of resistence. The bag is then secured by twisting the top and tying with rubber bands. The estimated period of sustainable oxygen level for this method is 20–24 h.
Packing rates depend on age and size of fry, duration of transport, temperature control system, nature of container, and climate. If the temperature in the plastic bag is maintained between 19 and 23°C, about 500 fry size of 2–3 cm can be packed per bag with good survival rate after the 16 h transport period (Table 16).
