From other threads I have read its not suitable for front loaders which is why I trialed it in my old washing machine that we use for woolens.

If you need to soften your water in the front loader try some vinegar (yes it works) or some Lectric soda just a teaspoon dissolved will be enough.
Ok, I'll keep using my vinegar then - I just thought if there was something that made things even softer I'd try that.