What treatment for new Pergola?
I've just had a new pergola installed using pressure treated "Canadian Lumber Stock" or something like that - it's the wood that looks like joists but has rounded edges. Anyway, I like its light colour so don't want to stain it but I do need to finish it with I'm thinking a clear preservative. There are markings on the wood so I'll need to sand them off but in my searches for a suitable finish I've become confused - do I go oil-based or some other finish? What have others tried and been happy with? I did have new sleepers in my last garden that I loved as they aged and became grey but as I was leaving, they had started to crumble so I want to avoid this (having spent a fair bit on my new investment and it's raining now!).
Thank you for ideas,