It's one of the tigers- Helodes i think. Have a Google.
This is the loach being bullied by your BGK?? These are in the upper-level for grouchy loaches. Once it gets settled it may kill your knife, so pay attention. I lost an overpriced BGK to less angry Botia species. One day knife is on top doing the bullying, next day the wrong button gets pressed and it's gills get sucked out. So has been my experience.
These loaches also do way better in groups- minimum 5 tends to be the recommendation. Lots of current, very clean water, soft sandy substrate etc... Make sure he's in the 125 as these max out approaching a foot and are very (very, very) active. They also grow a lot faster than clowns. Colours are fantastic if/when they are happy- tail goes bright orange.