Seriously Agressive Male Bumblebee Goby Is Possibly A Daddy

We had (note verb tense) 6 bumblebee gobies in my son's tank, we've had them almost I year I guess and they'd all picked their perching spots in the tank and apart from the old tussle and the odd nipped fin or two they got along absolutely fine, until last week.

I don't see my son's fish that much but he mentioned early last week that some of the bumbles were getting picky about their food. It's happened before so we did what we've done in the past and skipped a feed, usually this sorts the problem out. This time it didn't so he asked me to come and watch feeding time and what I noticed was that some of them had very depleted dorsal finage. He lacks attention to detail but the nurse in my never dies.

They really are a quarrelsome fish so this isnt actually that unusual but I noticed one or two had clamped tails, which is unusual. The puffers and the ottos looked absolutely fine but we decided to treat the tank with esha 2000 just in case.

They didn't get better at all and started to get very grey round their muzzles all except for one which has (note verb) very deep rich orange stripes, the others were more yellow. The orange bumble had no damage at all to it's fins.

Dan went on a civil war re-enactment thing this weekend and left me looking after his tank. {5 tanks to clean on my own YAY!!!) One of the bumbles died shortly after I did a water change.  I spent more time than usual watching his fish to try and see what the heck was going on and what I saw was the orange bumble REALLY SERIOUSLY attacking another bumblebee and I noticed this behavior all over the weekend. I resorted to putting the 2 most damaged in 2 fry cages within the tank and 2 in the quarantine tank in the hope they'd recover but unfortunately they all died. They were struggling to swim at this point which was quite horrible to watch and was why I decided to move them, although I think it may have hastened their end.

This orange bumble was shooting out it's cave and attacking any other bumblee which had the misfortune to get too close. Then it zipped back into one of the caves and its been hiding there ever since, coming out at feeding time only and then zooming back.

My son was absolutely gutted when he came home and I had to tell him his fish had gone, then he did some googling and what we think has happened and I'm happy to stand corrected is that the orange bumble is a male and he's successfully mated with a female and he's now guarding eggs in the cave.

If it is the case, we're both VERY suprised as we were led to believe they wouldn't breed in hard water so we never made any plans for them to breed. If it is the case and the fry hatch chances are the puffers will get them OR should we try moving daddy bumble and his house?

edited to add: he's picked the only cave in the aquarium that faces the back of the tank so we can't see whats going on in there, we only know he's in there when he nips out for a feed.

It was just the bumbles Sue, the puffers and ottos are fine and the male is back to his normal self again, although he's looking a tad lonely

I had a serious think about this and the only place I could put his cave is in with my baby celebes and I'm not putting him in there with them or I could take all the endlers to my MA but it's probably too late by now I'm guessing.