Got jellyfish season there? Otherwise, shouldn't have any issues with jellyfish.

Big fishes don't really eat you. The ones that you should be afraid of is the Titan Triggerfish. And a lot of small fishes can be quite aggressive too, like nemo clown fish or some white color gangster fish that bite me and made me bleed in Tenggol few months ago. It was hardly 4" long.

If you're interested in freediving, there is a proper course for it where they will teach you the correct techniques on how to freedive. Check out AIDA freediving courses.

Go youtube titan triggerfish attacks and see. A lot of snorkelers don't know how scary that fish is.

I also dunno what is it called. One of those small fishes la. I just call them gangster fish. But those fishes attack also nothing wan la. You'll just get some scratches only.

Plane one hour flight only la. Only place you can snorkel in west coast is Langkawi.

As for triggerfish, it's not always aggressive, but can be when it's protecting it's territory. And it's territory is an inverted cone shape, so even if you are on the surface of the water like most snorkelers are, it'll still attack you.

The last I went to Pangkor was 7 years ago. That time go for banana boat only, water cannot see anything also.