Originally Posted by 1077
What will get stuck under marbles is uneaten food if not removed with siphon or turkey baster.Many,,myself included, believe fish are not accustomed to light reflecting back from the bottom of the tank off shiny objects such as marbles or some of the smooth shiny rocks that some place in the bottom of their tanks. Is possible they aren't playing with the marbles as much as they are attempting to move them so that light doesn't reflect back at them.
Which is exactly why I'd never use marbles, gemstones, etc. They may be pretty to look at but as far as fish are concerned it should always be function over fashion, IMHO.