Swamp Cooler Temp vs Fermentor Temp??

I have my swamp cooler at about 65*, what would my fermtor temp be at roughly? I have heard that the fermentor is roughly 5* above the ambient temp during fermentation. Is this the same with the swamp cooler? I am aiming for roughly 66* for my fermentation temp, if so does this mean I should have my water temp in my swamp cooler at 61*? Please help as I am trying to avoid off flavors above 70*.

If the water level is up to the beer level, you can basically take the water temp to be the beer temp. Water has three orders of magnitude and then some more heat density than air at sea level.

My swamp cooler isnt covering my entire fermenter, maybe 4ish gallons. The fermstrip at just below the 5 gallon mark is usually a bit higher than the water temp (5+ degrees), but I wonder if the top of the beer is warmer than the bottom. I'd imagine this is the case.

But it's a great practice even if you can't hit/determine your temps spot on, because the temps arent likely to fluctuate much, compared to being out in the open.

OK so if I have the water at around the 3 gallon mark I should have the water temp at around 60* to hit 65ish* right? (help with the math is greatly appreciated)