Because bandensis naturally lay their eggs in rocks, tumbling is not necessary but they do need a gentle current to keep algae away. I did tumble mine for a short time after communicating with @Bret Grasse MBA . One thing the article in the Monterey example does not make clear is that they stop tumbling them when they are close to hatching.
I'm going back. At the time I was here I got eggs cuttle fish. I found a supplier in the Netherlands. This is the company Dejong. From the first attempt I saved only one squid. Now it is about 3 inches. I feed her live and frozen shrimps. Eats me out of hand. It is truly beautiful. I bought two more groups of eggs. There were 22 pieces, 13 of them were born. I feed the living Mysisem. So far, they eat it all. I am buying a live Mysis and live shrimp. I feed on the young from the Peacock eyelets. Can you please advise me what size I can put cuttlefish in one tank? Cuttlefish are cannibals?
We do see aggression with cuttlefish and the amount of space and hiding place in the tank seems to be one of the important factors (as well as the male to female ratio, more females seems to be best). While young the attacks are more about claiming mates than any interest in eating each other and are usually not fatal. As they age though, the aggression becomes more pronounced and the damage more likely to be lethal. There has been an anecdotal report that feeding squid may cause them to start considering attacking each other as food but this is untested.