Two coins, and only one of them is private

Nexus lets you pay in Bitcoin or Monero. They are not equal on the one thing that brought you to Tor, so it is worth understanding the difference before you fund anything.

Having both coins on the table is convenient, but convenience is not the point of a hidden service. Privacy is. On that measure the two coins are miles apart, and the choice matters more than the small difference in fees or speed.

What Bitcoin leaves behind

Every Bitcoin transaction lands on a public ledger that anyone can read and that never forgets. The sending address, the receiving address and the exact amount are all there permanently, and firms are paid to trace those records back to real people. Bitcoin is fine if you already hold some and you understand that the payment is not private on its own. It is the wrong default for anything sensitive.

What Monero hides

Monero hides the sender, the receiver and the amount at the protocol level, on by default. There is no public trail to follow because the network never records one. For the kind of purchase most people come here for, Monero is simply the correct coin, and it is the one Nexus treats as first.

Funding cleanly, either coin

Whichever you use, do not send straight from an identity-checked exchange into the market. Move the coin into a wallet you control first, let it settle, and pay from there. For Monero, Feather on desktop or Cake Wallet on a phone are easy and both route over Tor. For Bitcoin, hold it in your own wallet before it goes anywhere near an order.