Aeration of sea water with three different aeration devices at the same air flow rate (1 L/min.)
Porous resin airstone
Mili-bubbles are released from innumerous fine pores with about 150 µm of the airstone made of resins, and rise up in the water vigorously.
Fine bubbles of 100 to 500 µm are released from the porous ceramic plate, but go up toward the water surface rapidly.
Micro-bubbles (referred to as fine bubbles of less than 50 µm of diameter) tend to be suspended in the water for a long time due to extremely low buoyancy.
DDHRS Nozzle of eco-Bubble can create not only micro-bubbles (approximately 14 µm of mean diameter) but also nano-bubbles (approximately 0.2 µm of mean diameter) at the same time (Hu & Xia (2018))．
Remarks) The sizes of the bubbles released from the nozzle changes markedly, depending on the water conditions.