Koi Pond Problems

My pond has got like a bubbly scum on top of the water. Fish are sitting at the top of water as if looking for air. Pumps and filters running as they should be. This has appeared over the last 2-3 days. I have lost 2 fish and it is not looking very promising. Any help would be grateful. Thanks

If you have lost fish, they may well be sick. Check at koivet.com for help.
It also sounds like your bioload may be too big, ie, you have too many fish or they are too big.
Has hot weather just arrived and the pond is heating up?
Try Microbe-Lift PL to clear the pond and to add some beneficial bacteria. That should help.
You can also swap out 25% of the water. Don't forget to add dechlor.

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