It is very possible to maintain a healthy 10g seahorse species tank, because I have one. It currently houses 2 kudas, 2 arrow crabs, 1 hermit crab, live rock, fake and real plants. They are extremely happy and healthy. If you have any questions I can probably help you out. If you want sea horses I say go for it, they are amazing creatures and i love having them. They are needy, but worth it.