I did my second wfp Job today (read my post and see the picture) There is a balcony in the picture, and I did the windows there, with a bucket of pure water with a drop of squeegiee off just enough to give it glide, the windows came up a treat in and out on the balcony. On the balcony is a french window a full glaced door and a side window, so in all the are seven windows for me to do on the balcony aloan.
Before I started my TDS was 000 and after seven windows the TDS was reading 116, so you would have to change a bucket of water so often you would be using just as much, so you may as well just do it wfp.