PBW on aluminium

[banjobrew]

Well.

I've just used PBW for the first time on my aluminium kettle as it was starting to look a bit stained.

I filled the kettle with warm water and added the correct amount of PBW but I didn't stir it and when I emptied the solution out it had crusted in the bottom. I've scrubbed and rinsed it well and it looks very clean on the bottom but not the aluminium colour but a chalky white. The walls of the kettle look untouched.

Obviously I should have mixed the solution better but have I now damaged the kettle? Is it safe to brew in?

Any advice would be great, thanks.