The FloraFlexu00ae 4" FloraCapu00ae is a patent pending revolutionary tool for top feeding that also helps eliminate algae. The FloraCapu00ae 2.0 was redesigned to give you a more consistent flow rate, even distribution, a slightly increased air flow, and improved stabilization. Place the FloraCapu00ae on top of your 4 inch rockwool cubes, maximizing your space in the vegetative cycle. Fill the cap with water and nutrients by hand or automate with FloraClips. Each cap features 13 flower designed louvers that deliver water, nutrients, and air to the medium while blocking light. The FloraCapu00ae strategically covers the top of the media allowing the root zones to dry at a more consistent rate and delivering the necessary oxygen your plants need to thrive. Algae disappears, healthy roots fill the medium, and blossoms multiply.