good fun idea for a micro garden , i wouldnt want to subject any fish to them though , my only concern is if they took off the questions are bound to appear " how many p-bass could i put in my bulb " it was only last weekend i overheard someone in a lfs asking the guy if a blue dempsey would work in his bio-orb ,( they where very small dempseys but just shows how little people research things these days before buying) they guy was pretty sick when the guy behind the counter pointed him in the direction of the white cloud minnows . lol