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I have surfed the web to try to find an answer to this question and had no luck. So, I hope someone here has the answer. I have recently noticed that the koi in my pond have been hanging out at the surface of the water. They seem to do it mostly during the time that the sun is on the pond (the pond only gets about 4 hours of direct sunlight/day. So, at first, I thought they were sunbathing. :-) But, I have never heard of a fish sunbathing before! My pond is equipped with a biological filter that I run 24/7. I also have a waterfall which, I'm sure, delivers oxygen to the water constantly. They don't seem to be gulping for air, so I don't think lack of oxygen is the problem. And, they otherwise, appear to be very healthy. I test the water on a regular basis, and all of the levels are within normal range. What's odd is that another pond enthusiast whom I work with asked me the other day if my fish were hanging out at the surface of the water. !!! He, too, had never noticed this behavior before. I want to add that last spring my pond was "blessed" with lots of baby koi! I lost a lot of them, but still have quite a few. So, I know right now I have too many koi for the size of my pond. (which brings me to another question of how to find homes for all of my babies!?!?) My co-worker has the same situation. Could this be the reason for the behavior? Again...they don't seem to be stressed or unhealthy or gulping for air. Anyone have any clues? Thanks!

Beth