Hi peeps, I enlarged my koi pond in my courtyard which meant getting a new liner. Had all my fish kept in 2 separate containers while I changed out the liner. Saved water from containers to put in pond. Ended up being about 109 gal of old water with about 600 new water. Kept the filter Iike it was for the bacteria. So now all of the fish are hanging out at the waterfall. Does anybody have any ideas to why they are doing this? Thanks for any help.