the grit should be kept as far away from the drinker as possible, and like i said previously you should only give pigeons a little at a time, a pigeon only requires a pinch with like shadow said with the feed. Grit can become dirty, from dust and even the slightest of moisture can be kept hiden within the grit in the driest of lofts.If fanciers leave grit in 24/7, it becomes dirty, and will hold some moisture, that may not be visable to the eye, and pigeons will refuse to eat dirty grit, if you do this procedure change your grit regularly every 48 hours, prevents the grit from becoming dirty and holding mositure. The bath situation has nothing to do with grit, so cannot see the relevence this has to making the grit to with hold moisture ?