Aquatic Animals and Plants Need Dissolved Oxygen

The level of Dissolved Oxygen (DO) in water is a critical parameter in aquaculture, aquaponics, and hydroponic operations.  DO is required for plant and animal respiration. For plants, oxygen at the roots influences nutrient uptake.  For aquatic animals, too little DO and your livestock will suffocate.

DO is also important for root health, as low oxygen levels favor harmful anaerobic organisms that cause root rot (e.g. Pythium and Fusarium). Sufficient DO levels promote an aerobic environment favoring beneficial microorganisms. 

The HVO Approach

High Volume Oxygen has been making perpetual oxygen systems for commercial applications since 2011, and is now an established leader in the industry.

In 2017 we introduced a line of Dissolved Oxygen products that can be used in a variety of configurations to suit the needs of  large and small operations, in aquaculture and hydroponic settings. Following our tradition, all HVO products are modular and scalable, enabling the volume of DO to increase with your needs, while leveraging your existing investment.

HVO Products Link Together

The HVO DO product line is complimentary to our line of oxygen systems. If your environment requires perpetual oxygen (as opposed to using oxygen tanks, which, in addition to being dangerous, run out and must be replaced), you can use our HVO systems to make O2 gas, and our DO systems to make DO water. The two product lines are independent, so you can choose whatever means you prefer to generate oxygen for DO.

Natural and Safe

HVO's approach to DO is to steer clear of chemicals (such as hydrogen peroxide), poisonous gases (such as ozone), and small-scale / high-cost electrolysis, favoring a safer, more natural, and more effective method: compression.  Henry's Law explains the quantity of gas absorbed by water. It shows that the oxygen in water increases in proportion to atmospheric pressure. This makes it possible to combine water and oxygen under pressure to create high levels of DO. 

Our Dissolved Oxygen Products

Dissolved Oxygen Process Controller (DOPC)

The Dissolved Oxygen Process Controller (DOPC) is the brain of the HVO DO system. It measures the DO saturation, atmospheric pressure, and temperature of water, and may optionally measure TDS and pH, as well. These measurements are used in conjunction with preset DO thresholds to maintain saturation within a configurable range of values.

When DO falls below the low threshold, the DOPC energizes the AC and DC (coax) outlets for transmitting power and/or signals to various connected components. The components may include an HVO High Pressure Nano-bubbler, an HVO Flow Controller, an HVO Oxygen Generating system, and PSA oxygen concentrators. In addition, the DOPC may store its measurements in the cloud to facilitate remote monitoring and alarms. This enables you to record and constantly monitor dissolved oxygen levels so that you can provide perfect oxygen levels on-demand, using a computer-controlled, fully automated solution.

  • Dimensions: 10.5" x 6.25" H x 6.25" D

  • Weight: 8 lb 2 oz

  • Power: 120 vac, 15 amps with 20 amp breaker

  • Features: 3 AC outlets @ 5 amps ea, 2 DC outlets @ 24v ea


High Pressure DO Nano-Bubbler

The nano-bubbler combines water and oxygen under pressure to produce supersaturated DO with levels of 400-500% or 45 - 56 mg/L. The product has a 3/8" OD push-to-connect for 100 PSI oxygen input, a 3/8" OD push-to-connect for DO output, and two fresh water inputs -- one with a 3/8" push-to-connect and the other with ball-valve controlled garden-hose fitting. The nano-bubbler produces up to 100 GPH / 2,405 GPD in "recirculation mode", and 200 GPH /  2,880 GPD when attached to a pressurized water source.

To increase capacity, multiple nano-bubblers can be connected in a single system configuration via the DOPC (see above).

  • Dimensions: 15.5" W x 15" H x 13.5" D

  • Weight: 43 lb

  • Power: 120 vac, 5 amps

  • Features: 3/8" push-to-connect, ball valve with 1/4" MPT


HVO DO Flow Controller

Used to control the flow of either water or oxygen, depending on the particular configuration. When connected to the Nano-Bubbler, it controls the flow of DO water to the target water reservoir.

When connected to an oxygen source, it controls the flow of oxygen to a high-pressure micro-bubbler or a low-pressure diffuser (e.g. bubble-stone). The unit receives power from the DO Process Controller to gate or un-gate the flow of water or gas. There are two pairs of input/output ports, so this product can operate two sets of inputs.

  • Dimensions: 8.5" W x 4" H x 5.5" D

  • Weight: 5 lb 5oz

  • Power: 120 vac, 50 or 60 hz

  • Features: 3/8" push-to-connect (4)



Sample Configuration

The configuration below shows all of the HVO products working together to form a self-monitoring, set-it-and-forget-it, DO generating solution for a cloning operation. While the photo shows a single rack, this system is capable of supporting 10-12 such racks with just these components.

Components shown: On the far left there are two Philips M10 oxygen concentrators. In the center there's a nano-bubbler that has a DO process controller and a flow controller stacked on top. To the right you see an HV 30 gallon O2 system. A 3 outlet relay box for the HV 30 is shown on top of the rack.

Facts about Dissolved Oxygen (DO):

  • DO is gaseous oxygen (O2) dissolved in water

  • The amount of DO in water varies depending on salinity, pressure, water purity, and water temperature

  • Water that is low in DO can asphyxiate aquatic animals and plants

    • Aquatic creatures need oxygen in proportion to population density and their metabolic rate.

    • Oxygen-deprived root systems produce ethylene, which causes cells to collapse, increasing susceptibility to disease

    • Anaerobic (low oxygen) conditions foster pathogenic bacteria and kill off beneficial aerobic bacteria, which leads to disease

  • Water that is "supersaturated" with DO is highly beneficial to aquatic animals and plants

    • Accelerates root growth

    • Increases root mass, causing more fine root hairs and healthy root tips

    • Improves transpiration, which is dependent on oxygen

    • Kills anaerobic bacteria, and fosters the growth of beneficial aerobic bacteria

    • Reduces biofilm buildup, decreasing system maintenance

    • DO made from O2 does not introduce nitrogen, which can be harmful to aquatic animals

  • DO increases crop yields by 5-96% depending on crop type

  • DO increases water efficiency by nearly one third, as plants hydrate more efficiently