Got my 12th one last night. So with all the hours added up it looks like this broken down based on the times I recorded:

Atma of Fish: 10 hours
Atma of Bull: 7 hours
Atma of Twins: 5 hours
Atma of Scales: 4 hours
Atma of Crab: 3 hours
Atma of Goat: 2 hours
Atma of Archer: 2 hours
Atma of Ram: 1 1/2 hours
Atma of Water: 1 hour
Atma of the Maiden: 30 mins
Atma of Lion: 30 mins
Atma of Scorpion: 30 mins

So it was about 37ish hours of pure atma farming from Thursday evening, over the weekend, to last night when I finally got the last one (atma of Twins). I did not account the breaks I took running coil and HM dungeons.

So the best was getting two in one hour and the worst was the 10 grind in lower la noscea as I stated in a previous post.

So it RNG can very so I hope this helps with people how might be a little discouraged after getting nothing for hours of FATE grinding.