how to remove algae from rendered walls?

[Mazonas]

I see green and black algae at the bottom of my external rendered walls.. whats the best solution to remove in a cheap/domestic way NOT discolouring the render?
I hear spraying with bleach would possibly discolour the render and is best to avoid it..
what about vinger+water spray? if so, whats the best vinegar to water ratio for the solution?
also, would the regular ordinary weed killer spray (bought from shop) remove the algae?
thanks.
and no matter what solution is used, does the wall need being washed with water later on after solution is spayed and applied onto it?
thanks.

[mudmouse]

I have used this on rendered walls with great success. It does rely on the render having maintained its original colour

https://jarder.co.uk/jarder-spray-leave ... er-5l.html

After it has done its stuff the rain will wash off the wall and leave it clean.

I thought I had some before and after photos but I cant find them.