Cowfish release toxins when they are threatened and die... there dumb and fun to watch swim. Mine got trapped in the castle tower, sadly... and didn't find it until weeks after it was missing.
Yes, u can... for a 3 gallon get five pounds of live rock... but just go through the live rock VERY carefully... You don't need really special anything except hitching posts. With almost all seahorses, unless captive bred, u will probably be feeding live. However please don't buy wild caught... get captive bred.
!) Eat frozen Usually
@) Arn't offecting the population in the ocean ( seahorses are comming close to being endangered)
#) Won't have such a great chance as carrying diseases and that kinds of stuff....
For such a small aquarium, buy a small bag of live sand... it will only help u know... just make sure u don't skimp out on things... e-mail me if u wish...