I've bred amano and raised them successfully by having the mother in a 2 gallon plastic hexagon tank, 78°, in hard water 50/50 of tank and dechlorinated tap.
Left her there until she either drops eggs or they hatch. I then put her back into the main tank.
I don't even measure my salinity anymore. I dump 1 cup of salt per 2 gallons straight into that tank, slightly stir for about 5 minutes and let the air do the rest. Slow medium sized bubbles.
I leave them there until about half or so morph.
Attract them to the side with a light and siphon 50% of water out. Fill back up with freshwater tank water.
Let sit there until they all morph.
Net out and put into a 15 gallon grow out with 100% freshwater tank water and grow them out.
Slow medium sized bubbles.
0 salinity until eggs/larva dropped
Guess 33ppt salinity
Guess 15-18ppt when half morph until all morph
Then to 0 salinity and put in grow out tank.
Oh, I leave a light on the egg/larva tank on 24/7 and don't feed anything
The 24/7 light grows enough diatoms for them to eat and morph off of. Afterwards in the grow out tanks there is plenty for them to eat.
Good luck, 2,000 amano eat a lot and can be a bit to get rid of them.