What is a stinngind sea animal with tentacles?

There are many stinging sea animals with tentacles! To help me narrow down the options, could you tell me more about what you're looking for? For example:

* Where did you see it? (Ocean, lake, specific region)

* What size was it? (Tiny, small, medium, large)

* What color was it? (Red, blue, clear, etc.)

* Did it have any other features? (Bell shape, long trailing tentacles, etc.)

The more details you can give me, the better I can help you identify the stinging sea animal you're thinking of!