erm... ok, scratch that idea lol. it turns out you can't have coral with seahorses, and since i'll almost definitely turn this reef at some point... that won't work lol. also, most of them don't eat frozen or flake, so i'd have to raise brine shrimp... also not an option lol. i could technically have just two, but seeing as they're not compatible with my other fish... i'm declaring them a nono. lol. i guess i'll just stick with the clown, unless someone else has a better idea.
Dwarf seahorses are not the easiest to keep. Reason being there main diet is copepods which you will never be able to supply enough of in a 10-gallon tank unless you had a very large refugium or buy live pods they will get hungry. Live baby brine can sometimes be used as well but it still requires you to provide a live food source. The lifespan of dwarfs is also a little over a year. If you want seahorses you should buy captive bred horses that you can feed prepared foods (need to be fed twice a day ideally). You will need a 30 gallon tank minimum for most of the common ones. SHs can be kept with corals but nothing aggressive because the SH will "hitch" on it where it might get stung and/or eaten. This would be even more important with dwarfs due to their size. This is an excellent source for CB horses...
ya, but yasha gobies are probably the most expensive goby out there (actually seems the price has dropped since I last looked, they were always $80+, now I see them for $40 online) and notorious for jumping out of tanks. They are also one of the most difficult gobies to get established in a tank but once you get past the initial 30 day hurdle they usually live a long time. If you go with a yasha in a 10G then a glass top is pretty much required for them, netting/egg crate will not stop them from jumping. I would probably recommend doing a couple yashas with a pistol shrimp vs a yasha and yellow just to make sure to avoid any potential aggression issues between gobies. You could do a yellow clown goby instead of a yellow watchman and that would be a better combination.