This fish was hiding among some hard corals.
In the deeper pools were some of these fishes. I have no idea what these fishes are.
This fish with its face stuck under a coral is probably a False scorpionfish (Centrogenys vaigiensis) which belongs to the family of groupers (Family Serranidae).
There were lots of Cardinalfishes (Family Apogonidae). 
There were lots of assorted little fishes swimming near the surface, causing annoying ripples on the clear water surface that makes it difficult to photograph the submerged animals.
Tiny half beaks (Family Hemiramphidae) also float the surface, often mistaken for twigs or bits of rubbish.
Bottom-hugging gobies were plentiful, like this pretty camouflaged goby.
The beautiful Head-stripe goby (Amblygobious stethophthalmus) is generally only found near reefs. It was previously called the Byno goby.
This poor fish chose the wrong pool to shelter in at low tide. It was still alive and the tide turned soon after I saw it, so I think it's alright.
Our favourite fish sighting is of course 'Nemo'. The False clown anemonefish (Amphiprion ocellaris) lives in a sea anemone. This one was really tiny! Marcus and the rest saw another anemone with bigger anemonefish and Marcus observed one had laid eggs too!Fishes seen by the others include flatheads, toadfishes and Ivan saw a fat snake-eel. Good thing we didn't come across Mr Stonefish.
The shores of Sisters were full of little octopuses, actively going about their business in the dark.
There weren't any nudibranch sightings today, to Chay Hoon's great disappointment. But the hairy green seaweed (Bryopsis sp.) was in bloom, and so were the tiny little slugs that are often found on this seaweed.
I saw this odd little 'onchi' (Family Onchididae) on the rocky shore. Hmm, I've not seen one like this before. I have no idea what the little red thing in front of it is either.
It was really nice to encounter once again, this long pink sea cucumber that I've only seen so far, on Sisters Island and on Pulau Semakau. It hides under coral. I'm not really sure what kind of sea cucumber it is.
Another special find was this large feather star that was stranded on the shore. It fluffed up when I put it back into the water.
As the tide came in, Ivan finds a carpet anemone (Stichodactyla haddoni) with a pair of anemone shrimps (Periclimenes brevicarpalis). This is my first time seeing them on Sisters Islands, although they are commonly seen on some of our other shores. Marcus spots some parasites on the mama shrimp! My back is too weak to take that kind of close up, so we'll have to wait for his photos.The Sisters Islands is also home to a wide variety of hard corals and mushroom corals were particularly abundant today, and I saw some special hermit crabs today too. Chay Hoon also saw the Yellow-lipped sea krait (Laticauda colubrina)! That's great, I haven't seen one for a while.
As the sun rose, there was a humungous bout of screeching and screaming among the wild macaques that live on the island. But we didn't see any of them, and they didn't run off with Marcus' bag.
