apteryx54's Identifications

Between 2 to 3 mm.
3 m depth.
13 degrees
On old encrusted metal beam lying on the sandy substrate under the wharf.
There were at least 10 + on these hydroids growing on the clump of sea tulips.
The Doto were laying eggs and all the ones I saw had the brown speckling markings on them as per @apteryx54 observation on 23.5.2023.
https://inaturalist.nz/observations/163248687
I didn't get as good as photos as Richard there was a current and were hydroids in the way but still am posting observation for recording.
There are two in the last photo laying eggs, one on each frond the back one is upside down.