An insect culture maintenance system includes a sequence of open-ended cylindrical tubes joined pairwise alternately at their tops and bottoms using multiple dual-cap connectors. Each dual-capped connector has a channel from an inside of a first cap to an inside of a second cap. In use, connectors that cap the bottoms of the tubes are filled with insect food media, while connectors that cap the tops of the tubes are open. As a result of this design, adults pass from one tube to the next through the top dual-cap connectors, while larvae pass from one tube to the next through the bottom dual-cap connectors, resulting in propagation of subsequent generations of insects through the sequence of tubes.