Adee,
Have a look here:
https://forums.saltwaterfish.com/t/315559/seahorse-compatibility-chart
And here:
https://forums.saltwaterfish.com/t/301907/sh-tank-basics
For your basic reading. And come visit us here!
https://forums.saltwaterfish.com/f/36/seahorses-pipefish
We're all friendly. More or less.