Cleaning the roof.

[ChrisL]

My go-to solutions are:-
Milton's for algae
Sodium hypochlorite (from agri suppliers - strong bleach)
Johnsons baby shampoo, the blue one. (No salts)

And microfiber cloths.

Sodium hypochlorite will damage any aluminium parts like skylight frames, it causes pitting and the formation of aluminium oxide.

 

[TheMobileWanderer]

Sodium hypochlorite will damage any aluminium parts like skylight frames, it causes pitting and the formation of aluminium oxide.

Thanks ChrisL
I've edited my previous post to avoid confusion. I wasn't aware of that coz it's not cropped up in my world.

 

[ChrisL]

It's a bit embarrassing admitting how grim the roof was on my van, but I have some mobility issues so can't get up on the roof to do it myself, a very nice young warden did it for me in exchange for several beers
This what it looked like part done. we used Jennychem.