Maybe not YoYo Loaches?

[Fishman Dave]

Fighting like that occurs more often when they don’t have a large group where a true hierarchy can be formed with the largest female running the group and generally keeping others in check and overseeing disputes.
Another very similar botia when young is eos and many of the young ones are bought thinking that they are modesta as they often have the blue body colour and faded red fins, however they are not as tall fish, with slightly shorter fins and only grow to around five inches. These are a little more solitary and a lot more “fighty”.

 

[tiger15]

Sounds like I might have eos instead of modesta as the behavior fits the description. https://www.aquariumglaser.de/en/07-carp-like-fishes-1-loaches/yasuhikotakia-formerly-botia-eos/ Both would be sold as red tail Botia in US. I start to wonder whether my berdmorei is truly berdmorei as there are many Tiger loach look alike. It has red fins but the body pattern is slightly different from the OP fish.

 

[Fishman Dave]

Modesta has 9 dorsal fin rays and eos has 10 or 11 so if they were to stay still long enough you should be able to tell.
Also same often here in the uk, sold as red fin botia.

 

[Midwater]

I think the most obvious difference is that Eos are nice looking proportionate loaches and Modesta are battle tanks.

 

[A201]

I agree, Modestas are thick and powerfully built. Although physically similar to Clown Loaches, the Modestas are much more athletic.