Green conservatory roof

[giveup]

We gave our conservatory roof a good clean, but some of the glass/plastic( ',m not sure)
is stained green. How can we get rid of this. Any help/ideas greatly appreciated Thanks

[boxtops]

Is it moss, do you need moss cleaner?

[giveup]

It was just after the winter, i think it was algae but there are patches of green on the otherwise nice clean roof.

[AlBags]

Use a broom and RV (caravan/motorhome) cleaner.
If it is old plastic, it will get gradually worse and eventually stay that way.

[giveup]

Thank you both, it is ten years old but we always keep it cleaned, this is the first time this has happened.
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