Skimmer venturi assembly cleaning help

[gregzz4]

So, our venturi assemblies become built up with calcium carbonate, and we clean them

Do any of you have a quick soak method ?

I've tried vinegar, but it's too slow and don't want my skimmer offline for a long period of time
I currently scrape it with a jewellers screwdriver every week, but it's not the best way and I don't want to remove any plastic

Thoughts tips et all appreciated