Fresh Water Supply Line Size

[Invictus]

Can you please tell me the size of the blue and red pex water supply lines in my boat? Is this 15mm pipe or 1/2" pipe? And therefore what fittings (Watts or SeaTech or other) should I be using for replacement fittings? My goal is to change my fresh water pump and add an accumulator tank while retaining as much of the original setup as possible.
HIN: FMLT3123L516

Thank you!!