Solar oxygenator breakdown

[Carosmit46]

I bought a woodside solar oxygenator last September it worked very well,I read the reviews and was informed it would work through winter months,but after a couple of light frosts it stopped,I packed it away to wait for warmer sunny weather but still nothing. Too late I am afraid to return it,can anyone suggest an alternative method I only have a few goldfish floating planters and a water lily,I can't have anything electrical my pond water is also quite green,but I am hoping to add more plants as soon as I can get out and about,grateful for any help.