2"Ø UHMWPE rope has a breaking strength of ~375000lbs weighs 94lbs per 100' so about 4700lbs for 5000'
That said I have know idea if 2"Ø is the correct diameter rope to anchor one of these balloons.
edit: I was originally planning on adding in the weight of a high voltage transmission cable, but I'm on my phone and feeling lazy, maybe some one else will feel more inspired than I.