Lurk

if i can't touch the bottom, i get seriously freaked out. even if tanks arent that big, they're still bigger than me, and im a gigantic wuss about water

so submechanophobia then, tanks aren't that tall

submechanophobia is the fear of man made object partially or completely submerged underwater. this image scares me not because of the tank itself, but of the fact that the water must be deep enough to actually hold a tank

I think you might have submechanophobia instead