I understand that, but I'm sure there is a way around that.
I'm not saying she is wrong, but according to the figures on their website, (and the figures on my bag) She's wrong, and the calcium levels are lower than the stuff you are giving yours currently by almost a half!
In terms of the deposits, this is not necessarily evidence of too much calcium:
I took this from
https://www.theguineapigforum.co.uk...a-pigs-a-balanced-diet-incl-ca-p-ratio.37030/
Read the line that says:
It is important to work out a diet that suits your guinea pigs.
Be aware that it is normal for guineas to have milky/cloudy urine, and for it to dry resembling a powdery substance. The warning signs of far too much calcium in the diet is a thickening of this powder to a sludgy-type substance, and when it feels gritty to the touch.