I think with the bigger and deeper gaps between the gravel it traps more particle preventing them from floating around in the tank. I vac once a week and it pulls out a lot of matter.By using large gravel do you spent a lot of time cleaning it? Also do these guys do a good job of picking pellets off the gravel and finding it all?
I like to think of it as my poor man's Brassies.They're waiting for the feast lol their favorite hobby is gaining weight bro