if you want to set the cheapest possible fee rate without it getting dropped from mempools:
check the "Purging" fee rate from mempool.space/ and set something higher manually by enabling "Edit fees manually" option in the setting icon in the 'New transaction' window.
Take note that by setting that, your transaction will be at the bottom of the mempools and may take a while to confirm.

The lowest in the "mempool" slider will make sure that it'll have a good chance of getting mined however, it's currently expensive and quite at the low priority than "1mb from tip".

By the way, your transaction's amount (0.005BTC) does not affect the absolute fee.
It's the transaction's size (displayed as "bytes") multiplied by the "fee rate" (displayed as "sat/byte").