What is Tx0?

Tx0 is the transaction that needs to occur to uniformize your sats to go into a pool. Currently there are 4 pools of various denominations. If you initiate a mix of 0.016 BTC in the 0.01 BTC pool, Tx0 would create 2 UTXOs. One of 0.01 BTC and one of 0.006 BTC.