[brian nordstrom (As avatar)]

Na I dont think so , I've been doing it for years , all my scopes are refractors with good fully multi coatings . A good point though, Martin .Brian.

Originally Posted by MLyons

Wow! I would've thought that bleach (Chlorine - or Sodium Hypochlorite, the active ingredient) anywhere near Aluminium such as mirrors would be an absolute no-no.

Can you confirm that the Chlorine has no effect on the coatings?
I realise most commercially coated mirrors have a protective SiO coating, but that always has tiny pinholes through which a corrosive gas could penetrate and, over time, corrode the Aluminium under the SiO

I'd be inteested to see long term effects, if any.

Martin