Dwarfs are one of the most difficult seahorses to raise ... not for beginners.
The most common "starter" horses are the larger tropical species, with erectus and reidi being at the top of the list. There is more info readily avaialable for these species too. If you can go with a 29 gallon or larger tank, one of those species would be my suggestion.
If you have to go smaller, capensis and breviceps are available in the US, but are cold-water species and require a chiller.
Keep reading and keep asking questions. HTH
Todd
