Favoritos de fishmagnt

Very small demersal fish caught by hand net at the Lady Bay Road Reef Watch site at low tide. Pictured in small plastic container full of seawater, above the juvenile sea cucumber,in first photo (See earlier submission).
2nd and remaining photos in the above sequence only show the pink and white belly and ventral surface of the fish, due it's already moribund state (See below),but I include them as they show that the fish has rather frilly margins around the head and mouth, which would aid cryptism when in its natural habitat,perhaps sandy bottomed tide pools rather than ledges etc for which the pale base color would be less suitable.
I think the fish is either a juvenile goby or less likely a type of Clingfish (?juvenile or adult, unsure if so).
Unfortunately it may have been killed by my accidentally including a tiny jellyfish in the container for the brief time spent photographing each critter. Returned to the water in an almost moribund state despite having been kept cool and in shade.

Courtship behaviour ,only 2 adults involved,shallow tide pool with mainly sandy bottom and low rocky edges.
I've considered whether this might be 2 males vying for an unseen female's attention,but I favour courtship between opposite genders,partly because I would've expected to see a nearby female in the clear sunlit shallow calm pool,and partly because there are differences in morphology and markings between the two in the above images.I suspect the one with the most colourful fins and pale blue belly is the male but I don't know that.

[NB: Soon after joining iNat I posted an observation of that one fish with blue belly using 2 photos.Both taken on same snorkel ,date and site identical. Neither photo included a 2nd fish. For that reason I feel this current submission is not a mere duplicate.It includes a 2nd fish(probably Female),and shows behaviour not seen in the original submission.]