Blockchain – How much staking is required to make a single free USDT transaction on Tron?

I am using a wallet from tronscan.org to experiment with the Tron network and USDT tokens on top of it. I staked $200 worth of TRX. It’s not much, but I wanted to see the difference between betting nothing and betting a certain amount.

Now, if I try to trade 8 USDT from one of my wallets to another, I see a fee of around 3 USDT.

Can we add more to reduce the stakes to zero? How much do I need to get zero fees for just one transaction and how do I calculate it?