Appendix 5 Maintenance and cleaning of seawater system

Note: Refer to Technical Drawing – Pg 2.
1. Backwash first thing in the morning every day during months of hatchery operation. If needed (if water has high particulate matter), backwash several times a day.

2. For a continuous pumping system, cleaning of system should be done at the beginning of the season and at the end of the season.
End of season
1. Pump is turned off. Supply line is drained using drain valves located at lowest point.
2. Empty sand filter by opening drain valve. Remove sand and wash with fresh water. Let dry and store.
3. Clean sand filter and all parts with diluted muriatic acid and fresh water. Dry and store.
4. By SCUBA, remove mesh and drain of anchor. Block inlet with secured reinforced plastic bag. If possible, soak mesh and drain in a bucket of fresh water with a capful of muriatic acid to clean. Store until next season. If too fouled, replace with new mesh and a new drain.
5. Remove check valve, clean and place back in line.

6. Close all drain valves and pour gallons of chlorine into cleaner Y-junction after sand filter to clean supply line to hatchery. Let sit for a few days. Then drain line by opening all drain valves.
7. Once drained, close valves until next season.
Beginning of season
1. By SCUBA, remove mesh and drain of anchor. Block inlet with secured reinforced plastic bag. If possible, soak mesh and drain in a bucket of fresh water with a capful of muriatic acid to clean. If too fouled, replace with new mesh and a new drain.
2. Remove check valve, clean and place back in line.
3. Pour gallons of chlorine into cleaner T-junction in pump room to allow seepage into the inflow line. Let sit for a few days.
4. Set up sand filter with sand following dealer’s instructions.
5. Chlorinate supply lines to hatchery as at the end of the season (see Point 6 above).
6. Remove bag from inlet hole, install cleaned or new drain and mesh.
7. Turn pump on so as to pump water through and send to last drain valve on supply line for 24 hours at least to remove all chlorine residue.