You mean like this:
People nowadays over complicate everything. Just jump in, get wet.
First off, you are not supposed to touch the coral and, secondly, jelly fish are not always present. I prefer diving with a rash guard and some .5mm neoprene shorts. I do not wear bloomers or swimming dresses (aka boardies, board shorts). If I need a little extra warmth I will throw on a neoprene vest.
Of course, despite my hate of wet suits, once the water temp gets below about 80, time to suit up at least in a shorty and around 76 I might want my 5mm and below 70 my semi dry and in the 50s and 60s, my drysuit.
Here in Coz a few weeks ago, water temp on my computer was 82 to 84 but it was an off and on overcast day so I was a little cool and tossed on my thin neoprene hooded top and was a toasty as could be. I love the water, I love being wet and feeling the water against my skin.
Later that day and several time while down there, had to do my swim workout, swam about a mile along the coast which was super fun. I just wore just my swimsuit and swimming goggles. But, yes, if jellies are an issue and in particular an issue with you then you will need a lycra full suit or a tropical wetsuit, or like many divers, deal with it. I can usually find a hole in jellie swarms, but yes, I get stung, and for the most part, I do not get wound up over it.
Vandenburg, shorts and rashguard:
Cayman and rashguard and shorts:
In the Keys in the summer, it is like a bathtub, it is common practice to just jump in with nothing but a swimsuit. You do not need your SCUBA Steve super hero uniform.
But, in some places, if there are jellies that are truly dangerous, yes, you will need appropriate protection.
N