Tail/grep only one ip from pihole.log

Not as far as I know, but I use this solution to bring some detail in never ending stream of log entries.
After you've installed the required things, in baretail / Preferences / Highlighting, enter the IP address you want to see in color.
Setting up the authentication keys is described here, section 4.10

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duckduckgo says there is a way:

tail -f /var/log/pihole.log | grep "<IP address you want to follow>"

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