Floating Green Guck after winter

[jerbru]

this was not a very cold winter, bubbler and heater always on. About 2 to 4 feet deep, 5' wide 8 ' long.

there is a green muckey substance floating on the surface. Water is muddy in appearance, not green. When I remove green blobs with a mesh it is more fluid than solid.

I am going to thoroughly clean and exchange the water. Lost one fish others seem OK.

Comments, Suggestions to prevent a reoccurance.

 

[Meyer Jordan]

Typical Spring algae bloom being fed by the nutrients that have accumulated over Winter. Normal occurrence until plants can grow out more and out-compete the algae. Doubtful that it had anything to do with the fish mortality.

 

[MitchM]

Age of the pond, accumulated detritus and nutrients will contribute to floating algae mats.
What is your maintenance routine?