4th day since the few zoea hatched

A few larvae hatched 4 days ago. I was hoping more will hatch, but nothing happened. I decided to transfer the larvae into the salty tank. The specific gravity is at 1.025 (33.2ppt).
I fed the first food for artemia. I will feed very little 2-3 times a day, since I have only about 20 zoea. The rest of the eggs should hatch in the next 10 days time.
I prepared a 2 liter bottle with salinity over 1.050 for the water changes, so I just have to add a little bit of already aged salty water to keep the 1.025 SG.