My Sim, Andi Handichick, married King Triton. They have been married for one year now and just celebrated their anniversary and are contemplating parenthood. I DID cheat and took King to CAS and aged him down to YA. I didn't want this love affair to be over quickly as they really are quite the cute couple.
I didn't like his scale color so I took him to the mirror in his bedroom and selected Change Scale Color. While there it brings up a color chart and you can pretty much make the different parts of their scales any color combo you wish. I chose shades of aqua for him. Then we went to CAS and did a clothing makeover. I kept some things, like his cute swim trunks, but mostly the clothes were horrible. I also made his eyebrows slightly darker and his nose in better proportion but the rest stayed the same.
He has never gotten dehydrated although he scuba dives almost every day with her. When he got hungry I just clicked on the kelp in his inventory and had him eat it. Mermaids will also eat raw fish so just carry fish and kelp with you and click on it when they are hungry.
I also didn't think being a star athlete was a good LTW so I changed that to Swimming in Cash since his wife owns a 5 star resort and they both gather and sell a lot of shells and sea stuff.
I'm really enjoying playing them. The only difference I've found is he does have to spend a lot of time in the water but easily accomplished in Isla Paradiso! He's learning to cook! I am disappointed there aren't any kelp recipes except for Sushi.
Still don't have Mermaid Island and apparently I can't get there with King now that he is my spouse.
I've found tons of shells! I think the guide has a map of where they are but I've just found them by diving a lot and really searching all the dive spots carefully. One of those helper things that show you where gems, minerals, plants, seeds, etc are also will show you where shells are. Check out the sands on all the beaches. There are a few there.
The ghost merman is definitely cool! Much cooler than the resident ghosts scuba diving.