so i was tearing down my water loop to clean it and i noticed that my tubes looked a little darker. i have blue tubing i swabbed the inside of a tub with a qtip and it came out dirty. it looks like build up idk from what maybe from the loop in general. whats the best way to clean that out i let it soak in hot water with vinegar it seemed to have cleaned it a little but not all that great. any ideas??