Allow me to explain. When I play a videogame, and I end up in a pool of water more than 5 feet deep, I litterally freak out. Especially if the water is foggy. For Example, HL1: All those Itchyosaurs. The moment I found out they existed, I instantly began to fear every body of water in the game. I can't even progress any further in HL:Opposing Force because of all the itchyosaurs. :c I'm even afraid of the pool in GM_Construct.
I don't really think of it as a phobia as much as deep murky water being creepy.
ITT: Creepy Videogame monsters.