Male Stiphodon Fight

Well, this is something I haven't seen before.
Two of the males stiphodons in the river tank are have a proper scrap.
I'm not sure if these ones are neon blues or cobalt blues, but both have gone very dark in colour, and things are very physical. They are putting in a lot of effort, biting each other, and their fins are looking a bit torn.
I've had a look for info elsewhere, and apparently this fight for dominance is not uncommon, but I was wondering if @Sue or anyone else with these fish has seen anything similar previously.
I'm trying to get more pictures, but it's not easy.

Mine will regularly have little chases but I've never seen a prolonged 'battle'.

The boys bumped into each other on a rock, but a bit of head lifting and fin waggling seemed to do the trick and there was no physical contact. Their fins are torn from the earlier fight, so I hope they heal.
The panda garras decided to have their usual pushing & shoving session for a while, then the bulldog plecs chased each other onto different rocks, but it all seems to have settled down now.
Let's hope things remain relatively calm from now on.

They also had a large water change on Sunday, so I guess it's possible.

Keep us posted, including on whether the female actually agrees to one of them pairing off with her (or whether she stays well clear of them after being unimpressed by their antics).