Cute Octopus at Rottnest island

We were diving at Rottnest http://www.rottnestisland.com, on 3rd April 2016 with the Perth Diving Academy’s https://www.perthdiving.com.au dive boat Lionfish and saw a cute octopus which I think was a frilled pygmy octopus (FPO). Check it out :-

If it was a FPO then it’s the first time it’s been seen on the West coast of Australia according to the Atlas of living Australia :- http://bie.ala.org.au/species/Octopus+superciliosus

But the trouble with identifying octopuses ( or is octopi? http://grammarist.com/usage/octopi-octopuses/) is that because of their ability to change colour to suit their background it’s very difficult to compare photos from different locations.