Piping Output of Shuf Command

Fairly new to Linux. I have a nixie clock that runs off of a Raspberry Pi. I would like to send a random sequence of six digits to it every so often to help prolong the life of the Nixie tubes. There is a CLITool program I found on GitHub that lets me display any six digits using the command CLITool xxxxxx, where x is any digit 0-9. So I tried creating a bash file with the line shuf -zer -n6 {0..9}|CLITool. The shuf command produces a random six digit string of numbers, but it does not seem to get piped to the CLITool. Like I mentioned, fairly new to Linux, so it could be something basic I am missing.