Stipulations

Production Stipulations

1. A. tonsa (and copepods in general) are fragile aquatic organisms that do not respond well to rough treatment, vigorous aeration, or the crushing effect of gravity.
2. Tank aeration creates bubbles which pop and launch copepods onto the tank cover and sidewalls. Water surface tension holds them there until dead. Aeration should be the least volume able to maintain >4 mg/L dissolved oxygen (DO). If the surface has an apparent “boil” over the airstone, air volume is too high.
3. Male Acartia utilize their antennae to grasp the female for mating. Rough handling, resulting in breakage of antennae, will reduce the apparent number of males in the batch and the overall production of viable eggs. Handle animals carefully.
4. Locally acclimated, wild collected Acartia tonsa may have slightly different thermal and salinity preferences. Adjust the protocols accordingly.
5. Acartia culture is not a monoculture, expect ciliates and other organisms.
6. Algae is cultured at 30 ppt, if culturing at lower salinity, add freshwater proportionately to the total feed volume to maintain stable salinity.
7. Artificial seawater is as productive as natural seawater for copepod culture, but is usually more expensive.
8. A. tonsa nauplii are usually fed 15,000 cells/ml Rhodomonas lens and 15,000 cells/ml R. salina once daily. Advanced copepodites and adults receive 25,000 cells/ml of each Rhodomonas species, with an occasional feeding of Akashiwo sanguinea at 150 cells/ml.

 

Harvest Stipulations

1. Always fill the stacked-sieve holder and wash bottles with treated seawater at culture tank temperature. Do not siphon copepods onto a dry freestanding sieve.
2. Always wet the Nitex mesh and remove entrapped air bubbles, before siphoning.
3. Always keep the sieves submerged. Copepods were not designed to tolerate gravity.
4. Water velocity through the sieves should never crush the copepods against the mesh.
5. As the tank water level drops, frequently rinse down copepods stuck to the sidewalls.
6. Water quality, DO, and temperature must remain stable for culture times to remain consistent and predictable. Use digital controllers for all heaters and chillers.
7. Exchange 30% of the tank volume weekly with new treated seawater to prevent metabolite build-up.