I am not a strong swimmer and I find the mask and fins help keep me afloat. If you plan to swim out to watermelon then I would get a float belt but if you are just going in off the beach you probably won't need it. Depending on the beach, the water is usually pretty calm. Hope this helps.

I bought one and brought it with... ended up using it the first swim and not once after that. Although it wouldn't be a bad idea to wear one and just inflate it if you really need it. I got a great deal on one on ebay.

I am a strong swimmer but still use one. I find it fun to stop and just float and watch the fish. If you don't want to buy one you can always rent.