Spain/Portugal/Gibraltar - Barcelona restaurants open on Sundays and Mondays

I will be stopping in Barcelona for 3 days in September on my way to meet friends in San Sebastian. Unfortunately, it will be from Sunday to Tuesday. We are planning on eating at Cal Pep and have reservations at 41 on Tuesday, but that leaves Sunday an Monday. Some of my favorite tapas places are open, but we would like one lunch and one dinner at a seated or fine dining restaurant. So far I have found Moo and Alkimia. How are they and what else would you recommend? Thanks!

Moo is a pretty nice place. btw I love San Sebastian.

I really liked Alkimia and one of the reasons I chose it was that it was open on those days :D
I tried the degustation menu, 12 courses perhaps? It was quite inventive and very delicious, I'd go there again in a heartbeat.

Thanks! How do Gaig and Gresca compare to Moo and Alkimia?

What is a good choice for Sunday lunch in Barceloneta?