Don't go. The standard room we stayed in had the m...

Don't go. The standard room we stayed in had the most horrible airconditioning I had in a hotel so far. Even turned on as cold as possible it was sticky warm and awful dry air. My girfriend and I slept really bad. I got up with a sore throat and a headache. Which passed as soon as I left the hotel in the morning. Also the duvet felt too plasticy for a 5star hotel. Any Motel One room gives a better feel and airco than this 5star hotel.
When we wanted to go to the spa, we couldn t find any robes in the room. The reception was not available on the phone. Even though we left it ringing for 5min. So we had to get dressed again and walk to the spa in our cloths. Appearently robes are only in the more expensive rooms.
My opinion: If you're thinking to book, because of the huge, impressive fishtank, then just go for a coffee in a the resto or buy a ticket at sealife. And book your night in a different hotel in Berlin. There's enough truly great 5star hotels around.
Breakfast was good and lavish. But then again I don't book a hotel because of it's breakfast.
Even though we had planned a late check-out to enjoy the spa, we escaped after breakfast and went for a walk instead.