These kits are the perfect addition to hydroponic system. A submersible pump placed at the bottom of a reservoir attached to little tubing that either continuously (or on a timed cycle by adding a timer) mixes the solution, similar to how the oceanic currents keep the water in the oceans perpetually moving. Mixed or moving water will allow the already dissolved oxygen in the water to remain stable in its concentration and also provide increased DO as the water mixes with air on the surface of the reservoir. Moreover, the movement of the water will prevent stagnation and reduce the potential of the growth of harmful anaerobic bacteria which cause unpleasant smells, toxins, and disease.
"Constant drip" is a more recent irrigation method designed to level out the availability of moisture, minerals and oxygen. Mineral-rich water is constantly provided in a slow drip to plants that grow in a rapidly draining media. The idea is to maintain a constant balance of moisture and minerals without drowning the crop. It can be somewhat tricky to consistently provide a perfect balance. On a hot summer's day, a large plant can transpire a lot of moisture, so water must be provided at a far higher rate than would be required on a cooler day for a small plant. This allows you to adapt your system to the needs of the plant, location or season.