Hello there, I was outside lastnight enjoying a cup of coffee after some tank maintnance, when I went back into my house for a re-fill, I noticed that my 180 gallon tank was a quarter the way empty....I had a lil' trickle of water coming down the back of one of my Aqua Clear filters and it drained that much in an hour or so!!! Bummer. I'm still drying the darn floor!!!