Water Treatment with Soft Water ?

Does anyone have experience of using treatment when the boiler contains softened water?
The Multitreat stuff I've purchased recommends 0.3% (3000ppm) for hard water, but no indication of how much to reduce this by if you only need the free oxygen grabbing property for rust prevention.
I've also read that treatment should not be overdone, but I can't find any information on what happens if you do.
Hence my question.

Chris

In my short experience, over doing the water treatment can lead to excessive priming, also over doing it over a long period of time it will build up around the mudring which sets like concrete from what I've been told, hence carrying out regular blow downs and washing out.

Having said that I know folks who dont use it all with little ill effects, although I suspect in the long term it will cause issues, although how long long term is I'm not sure

I must admit to only dosing generally once over a weekend rally, its not like it comes over in the steam (unless it primes) so what ever you put in will stay in the boiler accept when you blow down etc.

As I live in Scotland and have very good water I still use treatment in my boilers as it slows down corrosion my last steel boiler looked like new inside even after some years use
mark

Medium tea in the sight glass here in very soft north of scotland. Boiler inspector very pleased with 5 years in steam.