Has anyone else noticed fish species differentiating in each country/state?

[TheSwissAquarist]

It's such an abstract concept, but over the last couple of years I have moved around the globe (taking my fish passion with me) and have re- and destocked my aquariums. Fish from the same species behave so much differently in Switzerland than in Canada.

Comment if you have also noticed this. 

[drewzero1]

I don't have much experience observing fish outside of my home state, but it does make sense to me that they might act slightly differently depending on what's in the water where they are. Where I live we have limestone bedrock which puts a lot of calcium in the water, among other things; some fish really love that, others would rather not have so much.

(Side note: sometimes I forget that there are so many other substances in water, way beyond what our test kits even look for, and they can vary by region or locality. Water is never 'just' water!)

[Flumpweesel]

I think all fish have personalities and show learning so yes behaviours can vary wildly based on so many factors. 

It could be down to tank positions ages of fish and time with you in each set up. I suppose will affect them to.  And if tank bred or wild caught which will vary depending on your location no doubt.

But I have only kept fish in the country and only a very small area of that so my observations are limited.

Maybe we should all get one type of fish and test theory .