I'm asking about putting long lines on the bubbler to run down to your structure and have the blue rock thing disperse the bubbles down by your cover.
The reason that I am asking this is that I know that crappie are curious critters.
Story time: I was playing disc golf at a buddies place a couple of years ago and threw a driver into the drink. After the round, I used my buddies fishing set up which consisted of a weight and a treble hook. I went to where my disc went in and started casting a couple of feet into the water to try and find it. After about 6-7 pitches, I swore that I actually got a hit. I told my friend that I just got bit and he laughed at me. I threw it back and pulled out an 11-12" crappie. This moment has stuck with me so there is where this question is coming from.