this is my 10 gl at about 6 weeks. i have a bullseye pistol shrimp, a pom pom crab and a black seahorse. i also have a bunch of mushrooms as well as 1 snail and 5 blue-leg hermits for a cleanup crew.
honestly i think the sea horse should do just fine. I had a small one in my aquapod with lot of lr and stuff he could hang on to. He did just fine i had him for like 9 months than decided to give him up cause i missed having a reef tank but ya he lasted and it was one just like urs but smaller and just make sure u dont have alot of flow and check ur Ph and stuff like that to make sure they r good enough to have a sea horse. Beautiful creatures though and i like the ur tank. Keep it up :happyfish