Two Male Peacock Gobies Fighting..be Worried?

[watertown28]

Should this be of concern? I mean I have 5 of these gobies, 3 of them female, and 2 males.
 
For some reason now they are flared, and actually going at it pretty good. like sand kicking up as they circle each other and then go at each other good. I have not seen this from them ever. I only had em about 4 to 6 months, but this is kinda new and not sure what to take of this.
 
The bigger male seems to have some fin tearing going on too.
 

 
Tank is 55 gallons with only these 5 fish in it. More than enough room to hide or get away at least... not sure what is going on with them.

 

[betta fish]

I have never kept them before so not clued up on their behaviour but it looks as if they are gearing up to breed and they are fighting over the girls, your tank is nice and big so as you say they can get away from each other if need be I think they just need to sort out who is boss I would keep an eye if it goes on too long and neither gives up then they may be too evenly matched so you may have to look at removing one but just give them some time to sort it out, a few torn fins will heal, they are nice looking fish