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Sepia officinalis seem to lay eggs when they are smaller than when they are in the wild, not sure why... higher concentration of hormones maybe?? Anyway, they will be around 18 months old when they start to lay I think if you use a steady temp and keep them in doors however they can be much larger in the wild.
Females die after they lay eggs as well I think, and some ( s. pharonisis????) seem to guard the eggs when laid!