God this is such a. Niche lore post but like I need to post about it so bad
So in challenger deep, most merfolk do lay eggs like (most) fish do, save for the mammalian types. But in general they do come from Egg™ and they do go through larval stage to juvie stage to adult stage. And some of the lore I had been workshopping is that eggs are kept in special lil enclosures separate from the ocean itself until they hatch, some are even communal (like a daycare, if you will). I don't have a whole lot of worldbuilding on it yet but its a thing
And recently.. I have been binging a youtuber's videos and she has a lot of pet fish and comments on a lot of fishkeeping practice etc. And in one of the videos.... WAS a little device you put fish eggs/embryos in. It's an egg tumbler. It tumbles the eggs. Because if they lay still for long periods of time fungi can grow over them and they can die from that so... they literally put the babies on the fucking Trampoline Contraption for however long it takes them to hatch to keep them alive and healthy. And I cant stop fucking thinking about it also being a thing in CD like oh my god getting put in the pear wiggler is fucking real but its for your own GOOD
Here's a nice view i found of one of said tumblers but its also a really good timelapse of the egg to larvae stage for cichlids
