One of the problems presented to the aquarist by this species is that of egg-eating. In the wild, as has already been noted, tens of thousands of pairs spawn simultaneously, and in order to reduce the competition for their own offspring, a pair will turn around and eat some of the eggs being produced by neighbouring spawning pairs. The same instinct, needless to say, manifests itself in the aquarium, but in an aquarium setting, the only eggs present are usually those of the single spawning pair. Consequently, some of the pair's own eggs will be devoured. Special measures to reduce losses through this behaviour are therefore required if the aquarist is interested in obtaining as large a yield of fry as possible. Special 'egg traps' have been devised for the purpose - these may consist of evenly spaced glass rods in a frame, a layer of glass marbles on the aquarium bottom, or some other such device. The purpose of all these designs is the same - to allow eggs to fall through small gaps into a space where they will be beyond the reach of the adults, who are unable to pass through the same gaps. However, the speed of movement of the adult fishes is such that even with an 'egg trap' in place, a small percentage of eggs will still be eaten.