Lots of Buubbles on the rocks please help.....

[Hollybostick]

Our first winter with this pond and koi. The water has dropped to 50 degrees F and the fish have stopped eating so I stopped feeding. Today I notice crazy amounts of bubbles on the rocks and rock ledge that they sleep under. Have I not done something correctly? Please advise..... I don’t want to lose my koi. Thanks

 

[Lisak1]

I see bubbles from time to time on our rocks - not a cause for concern.

 

[GBBUDD]

plants / ie algae on the rocks bubbling is a sign of a healthy pond or one that could be starving for o2. generaly though it's the first plants need co2 to grow and when they have a good dose of co2 they give off o2 and when they do it usualy stays attached to the algae a while until it is pushed off by more o2. seeing as it's fall in your photo i'd say the extra nutrients leaves are rotting giving off co2 and that one area of algae is sucking it up the rest of your rocks look like they have a healthy coating of algae

 

[j.w]

@Hollybostick