There are two rooms at Carpe Diem, the only downside was that the soundproofing between the rooms wasn't brilliant, if the other room was a bit lively you could really hear them!
Danielle was really lovely, although I don't think she speaks much English so you probably need to speak a bit of French! The location was great, 5 - 10 minutes stroll to the river, the beach and the village centre with its friendly bars. Our room was perfect, with a big bathroom, our window looked out on some gorgeous sunsets (we were really lucky with the weather for early May!). Breakfast was your typical French stuff, croissant, bread, butter and jam, as well as some very good coffee. We would definitely stay here again, Grau d'Agde itself is a pleasant place and the beach is great, we had a fantastic meal at L'Astoria restaurant overlooking the river.