Heater hoses and quick disconnects

Hello all,

I was working to remove the EGR valve to try and clean it out and I managed to break the plastic quick disconnect on the heater hose that is nearby it. I attempted to remove the heater hose from the heater core so that I can take it with me to the parts store to get a new one, but I cannot, at all, remove the hose from the heater core pipe on the firewall. Is there another quick disconnect back there as well or is it just glued onto the pipe due to age?

Also, Can I just remove the quick disconnect and use a normal hose and hose clamp? Plastic quick disconnects seem like a less than optimal solution. Does anybody know the heater hose size I'd need to do that?

thanks !