Dwarf seahorses require live food and constant hatching of baby brine shrimp, make sure you are up to that task before you even think about dwarfs. There are 2 places that I know of that sell captive bred dwarfs, but I'm pretty sure I can't post it here due to forum rules. Do a lot more research on dwarf before you consider them. To raise pH you may just need more air in the tank. I have an open airline in my seahorse tank making large rolling bubbles. Honestly with dwarfs you should consider a slightly smaller tank like 5 gallons. 14 gallons is kind of in the middle, too big for dwarfs unless you have a huge herd and too small for the larger species.
I would make the 14 a softy reef on my desk and get a bigger tank for a larger species like erectus. Oh wait, that's exactly what I did do :rotfl: