system
Given the following post, respond as if you're commenting on Reddit:
human
ELIF: Why do things float towards eachother in liquids?

  I first noticed it with cereal in milk, when you put it in there the cereal clumps. I wasn't sure if it was the iron in the cereal so I tried bits of styrofoam in milk, still went towards eachother. I've experimented with this a bit and I'm stumped. I thought it might be something to do with the surface tension in the water/milk/liquid but I added dish soap to the water once to lessen the tension and they still clumped. 
  Then I was curious about it might be gravity pulling them together so I used two things of known mass and figured out the ammount they should accelerate and in practice they accelerate much faster. I am at a complete loss as to why this is and was wondering if anyone knew. Sorry about formatting weirdness I'm posting this from my phone.
gpt
Try to imagine it this way:

You have a piece of cloth stretched out. If you place a ball in the middle of this cloth, you're going to create a dip in the cloth. Place another ball at the edge of the cloth now, and it's going to be "attracted" to the first ball. 

The same concept applies, but you have the milk's surface as the cloth instead, and the cereals act as the balls. Each cereal actually 'dent' the milk surface, but it's just so small we can't see it. The effect is still there though, and thus each cereal would clump together.