Hotel Diament is more a kind of sanatorium than a normal hotel, but they have some good weekly arrangements. So it is worth to have a look on their pricelist, mainly in the outseason.
It is close to the Baltic Sea, but you should not expect anything other. In the outseason, there is nothing around in the village, if you can't be outside in the evenings (that would be in the outseason), you should bring some stuff for games or something like that with you.
There is a nice pool and sauna. They have many possibilities for different therapies (massage and so on).