coffee grounds in worm bin

I have access to unlimited coffee and tea grounds. How muck of these can I use in a worm bin? 100%?

Answer from BigTex Worms
I am SO glad you asked. Coffee Grounds can be used but absolutely not 100% more like 10% at the most. Coffee grounds will make your bin to acidic and can kill the worms. If you are going to try using more than 10% grounds, you must get a PH monitor to make sure you stay in the neutral zone.more info on worm bin ph here
Liz
BigTex Worms