The most common method for degassing hydrogen sulfide from drinking water is using tray aerators, which contact ambient air with the water. There are several issues with using tray aerators:

• Low removal efficiency of hydrogen sulfide, mainly due to poor contact between the water and the natural draft of ambient air;
   
• Exposure of drinking water to ambient air, which contains air pollutants, such as soot, chemicals, engine exhaust fumes, dust, bacteria, etc.;
   
• Negative removal efficiency of hydrogen sulfide, since growth of sulfate reducing bacteria (SRBs) on the trays can actually increase the hydrogen sulfide in the water, instead of reducing it; this was actually measured, as detailed in the testing described below;
   
• Lack of security of drinking water systems; tray aerators make the entire drinking water system vulnerable to terrorist-based poisoning of drinking water, since these aerators are usually accessible by staircase, alongside the water storage tank;
   
• Hydrogen sulfide removed by the ambient air can cause odor issues in the surrounding homes and result in corrosion of tanks, handrails, etc.