The rooms are like cells and the beds are amongst the most uncomfortable I have ever slept in. We were allocated a room without a balcony even though we booked one, and when we complained the stuck-up English owner implied he was doing us a favour by changing our room.
Our room was similar to a ski studio but old-fashioned and very poorly maintained: loose electrical sockets and fittings, poorly equipped and tatty. Even though this hotel is on the seafront, it didn't have any of the ambience that this implies.
The pool is small but adequate, although don't expect to relax there, as the loungers are padlocked to the adjacent patio area.
The only positive is the comfortable communal area and free wi-fi.
Andernos itself is quite nice, although the beaches are VERY tidal.
If I visited the area again I would stay in Lacanau or Le Moutchic.More