It seems like I'm always the one so I hate to say it, not that sea horses cannot be kept with corals, but in general for the long term health of both it is better not to mix the two. They have very different needs as incysor has pointed out. Hopefully you bought captive bread seahorses as wild caught have a very poor survivability rate due to parasites and the need for live food, were captive breed will consume frozen mystids and are generally free from intestinal worms. The prob is having the food available for them to eat and not blowing around out of their reach. Now IF you shut off the pumps when you feed and take other steps to ensure their health sure it can be done but it definitly complicates things. Sorry if this isn't what you wanted to hear but I really believe in specialty tanks in these sort of cases. Seahorses do not need a very large tank, set up a tank that is geared specifically to their needs, and keep your nano a reef tank. All this of course is just IMO?????