During the weekend I induced the spawning using light and it was quite effective. A good amount of gametes were shed (together with poop…).
I washed a few times before adding a couple of drops of 0.5M EDTA solution. Eggs did not show any cleavage stage a few hours after activation. On the next day there was a small number o embryos at 2 or 4-cell stage. Not significant.
On Sunday I made a 0.1mM EDTA solution and left the embryos for 1h at 10 °C and no shaking. No cleavage stages again, but on the next morning there were quite a few embryos in cleavage stages up to 64-cell, apparently.
Today I left the embryos for 2h in 0.2mM EDTA (exchanging the solution after the first hour). 2-cell stage embryos were already present a couple of hours after spawning. More embryos seem to be cleaving. I washed the dish many times and put the dish in the cold room (5-7 °C).
Sabrina helped to set a 4D recording with a 2-cell embryo that will go overnight.