Good Video
UBIK 2000 from Clover is a good product designed for its purpose to degrease it is not reccommended for windows and it will not kill algea of which he was cleaning the perspex roof.
We use Swift & Sure safe algae remover siutable for all surfaces to remove algae growth it is very cost effective to use, can be puchased in 2 x 1lt bottles as a super concentrate it is free from coshh regs and does not carry a warning symbol on label it is safe for humans, animals and plantlife, you can spray it on like in video or better still if you have a trolley system you can put an amount of product in container and dilute with pure water clean as in video then rinse off with pure water no streaks and beads off quickly, best we have ever used, 1lt of concentrate makes up to 50lts of ready to use product so very cheap at 0.39 pence per lire RTU + it does depend on nature of soiling but we give our operatives a ready mix in a 25lt drum and had no complaints just great results its also good for cladding cleaning/ exterior caravan cleaning and 100's of other uses.
Be very careful using TFR as most of them contain caustic and if left to dry and not rinsed can cause you a costly headache.