There are several synonyms for the phrase "drink like a fish." Some less vulgar options include "imbibe excessively," "binge drink," or "overindulge in alcohol." A milder alternative might be to say someone "likes a good drink" or "enjoys a cocktail or two." Other more colorful expressions might include "souse oneself," "tie one on," or "hit the bottle hard." Regardless of the phrasing, excessive drinking can have serious consequences and should be approached with caution. Moderation is key in all things, especially when it comes to consuming alcohol.