Clearly bands who force the mental imagery on you with pictures or actually using words like sea, ocean, tide, etc. have made an effect on you guise. It would be fun to find something that doesn't do that but i can't think of any offhand so maybe i will record some ocean metal, without lyrics, and only pictures of grandparents scattered throughout the booklet.
I'm also going to say Boris - Flood, even though i don't think it sounds watery but they used the word Flood, and maybe if you imagine flooding when you listen it will sound that way by association