Hello ARC,
After a hard day of working on the tank, my Deresa clam decides to reward me by spawning in the tank. Enjoy the video!
Believe it or not, my one female urchin happened to be cleaning the side of the clam's shell and she decides to start releasing eggs to join in as well. It's hard to see but she's moving all her tentacles towards the center and pushing them out at the same time to distribute the eggs. By the time I noticed she was doing it, I think she was mostly done so there weren't many eggs left coming out of her.
Here's a better video I took a couple months ago of the female urchin spawning. She's the one on the left. If you pay special attention, you can see the male releasing as well. It just looks like he's smoking on occasion.