Sargassumfish (that's her at the bottom left) lay what's called an "egg veil", a jelly-like ribbon that may be an inch thick, four inches wide and more than 30 times the length of the mom. Embedded in this veil are roughly half a million eggs. Mine laid one this morning and it can be seen here as a swirl of gelatin floating above her.
Here's an essay I did on this incredible fish back in 2009. And a video of one of mine swimming (scroll to the bottom, but read the rest if you want). And another of the fish that laid the veil today: