Thanks C!
My octopus is on its fourth week of captivity and it laid eggs last week. It is just the common octopus (octopus vulgaris i think). Unfortunately, the octopus died this morning

and I don't know why. So I placed the eggs near the aerator so that bubbles can pass through it, i don't know if this is the right thing to do to save them. I hope these eggs will survive.