[RegisteredUser]

Thats probably twice the anchor you would normally need.
A heavy anchor would be a 35lb..not kg..and one of the nexgen types like Mantus Rocna Manson Spade etc.
The fortress mentioned above is also highly regarded...and light. I have one as my 2nd.
id keep the 8mm 5/16s chain.
make the shackle connection stronger than the chain.

id sell that 55lb cqr....