Who do you pay the money to?
It seems strange if you're paying £170 per week and £80 per month, if they're both being paid to the home. If the £170 is paid to the council, then I can understand why.
I have Power of Attorney over a family friend and because of her savings and income, she has to pay over £1300 per month, which is paid to the council.
On top of that we pay the home for extra services, such as hairdressing, days out, toiletries, etc. This is anywhere between £20 to £60 per month.