Decapsulation Protocol:

Removes surface pathogens from Artemia cysts and prevents introduction of inedible Artemia egg shells to larval fish systems

By Dr Ian Bricknell

FRS Marine Laboratory

375 Victoria Road

Torry

Aberdeen

AB11 9DB

UK

i.r.bricknell@marlab.ac.uk

Add 32 g cysts to 920 ml fresh dH₂O, for 1-2 hours (no more than 2).

Dissolve 2.4 g NaOH in 10.56 ml fresh dH₂O.

Dissolve 4.93 g Tropic Marin (or any other good artificial marine salt mix) in 149.44 ml dH₂O.

Combine above two solutions to make the NaOH buffer solution. Cool to 4^oC.

Add 160 ml NaOCl (Aldrich; active chlorine between 6 and 14%) to 160 ml dH₂O

Prepare 320 ml 1% sodium thiosulphate (3.2 g in 320 ml)

Have plenty of fresh dH₂O for rinsing steps, and crushed ice available.

Then:

· Drain hydrated cysts into the 100mm plankton mesh sieve;

· Immerse sieve containing cysts in pre-cooled NaOH buffer over ice;

· Add NaOCl solution; stir continuously for between 3 and 5 min until cysts have changed colour from grey/brown to grey/white to orange;

· Remove sieve and rinse the cysts thoroughly;

· Place sieve in the sodium thiosulphate solution and stir continuously for 1 min;

· Remove and rinse thoroughly for approx. 5 min until there is no residual smell;

· Drain & dry; may be stored dry at 4^oC for up to 7 days or alternatively in a saturated brine solution indefinitely.