That whole 200 fish isn't the cap is completely wrong.
Lvling from 30 to 100 I counted. Except the days when I just didn't fish enough I went to 0 bites at 200 fish every day. I fished up to 3 shangs. Was exactly 200 fish every day
In fact I believe around last december SE actually announced that limit and said it would go down to 10 if you were under lvl 20.
Now that changed after I got ebisus. Went up to 220. Then they updated ebisus a few months back to make it "better." Now I get like 204-220 depending on what I'm fishing how many different things I'm fishing and zoning. Not a huge change but certainly didn't make it better.
Also for moat carp depending on moon phase 2-4 hours. Big range cause well at 50% my biterate on mules was like 70-80% at new/full moon I've gotten 100%
Right now I do trumpet shells. That is usually 12-16 hours to get max fatigue. Granted w/o ebisus that would probably be like 2 or more hours less since it will be less fish and be at the time when /recast is at the highest.
Um I did Cave chereaux for a while. That litterally took pretty much 18-22 hours but I would hit fatigue at 220. Damn 10% bite rate in the middle of the desert and being unstackable