Tidy Tent

[Tefler]

We've got a Tidy Tent - a thing to keep bikes, etc in in the garden. It works perfectly, but is covered in some sort of green algae, which looks unsightly and probably isn't doing much good to the material, either. I could do with some advice about what to use to clean the material. I need to remove the algae, but retain the waterproof nature of the fabric.

[Uriah Heep]

Try a good scrub using Persil or similar. If that does not work step up to a power washer. Depending on the fabric (canvas?) it might be possible to re-proof it with a can of what caravaners use on their awnings.