The Santa Cruz one, in the city center is nice and we'll located.
The only thing to know is that when you call them a few days before, they may say they are full, it can be a lie. They actually told us that last year and when we arrived there were a lot of free space.
also further away Las Galletas has a small private and quiet marina. This one was very friendly when we stayed. And clean. Many others had dirty bathrooms and old decaying docks (e.g. the Gran Canaria city one, yukie)