5 Gallon Reservoirs - Deluxe w/ water level indicator -- for Blumat SystemsDescription 5 Gallon Reservoir with water level indicator The main trouble people have with gravity Blumat systems comes from forgetting to refill the reservoir and letting the carrots dry out. With this simple water level indicator installed, you can see with a quick glance how soon you'll need to refill. If you already have a 5 gallon bucket system, you can just add on the water level kit.