If there were extra terrestrials on an ocean moon, what technologies would you expect them to have?

They would need a technology for toasting bread far beyond our own .

Swimming

Did they evolve there, or did they just set up a base there...? I agree with William - if you look at *our* ocean species, their bodies are torpedo-shaped for the most part, with no dexterity... And, making fire is a key point of development in a species progress - but, unless you’re Sponge Bob, you can’t make fire under water...
If it’s a species using the moon as a base - then, I’d expect them to have a series of floating platforms and habitats on the surface, with facilities to reach into the depths.

If there is any life on any of the planets watery moons such as Enceladus then it is more likely to be the very basic life but we simply don't know if:

a) There is any life in these oceans.

b) How far these lifeforms have evolved.

It is always possible that this life has evolved in a different form than that of humans and may have evolved considerably more than the basic forms of life.

We will never know until probes have managed to penetrate the icy surfaces of these moons.

Poseidon

It depends on their evolution and if they are native to that moon.

Let's assume they are native to that moon, it would mean they evolved in the ocean rather than on land like we did. That means they already had means of communications and detection of food and eluding predators. BUT that also means no need for shelter and lacking any real need of wonder with things like fire or sticks and their limbs are probably dedicated to swimming rather than inventing.

They probably have found ways to cultivate their food if they are evolved enough to do so. They wouldn't need light because they are use to the dark and "see" with sonar. They have no access to electricity not because it would short out, but rather being able to see lightning and trying to harness its power -- let alone finding resources to manufacture them.

Aliens are not exist. So none

Next to none. Without fire technology is next to impossible. Unless they had figured out a way to use vents on the ocean floor perhaps.

boats

A peg to put on their nose, and a set of floaties.

Cheers!

Ocean-borne species are unlikely to have technology because they don't have the manual dexterity necessary to create it. This requires a hard skeleton with digits and marine creatures are not likely to develop them. It is an interesting thought, however.

Whatever enabled their survival.

I find it difficult to envision an advanced aquatic civilisation. For instance, watch what happens to your smart phone when you dunk it in seawater?

That's why ultimately it doesn't matter how bright dolphins or whales get. Not only their morphology, but their environment pretty much precludes them from making any of our technological discoveries. They will fail to create any sort of specialised society no matter how many millions of years you gave them to do it.

Perhaps there is a way "up" for an oceanic species, at least one like cephalopods with lots of digits to manipulate things with, but their development path would be a long road, so incredibly alien to ours that I just can't imagine what form it would take.