Aquaculture

Feed sets the oxygen bill. We pay it at the bottom of the pond.

We size the oxygen plant on your peak feed rate, not your pond volume, then prove it on one pond or tank against an untreated control. See how a pilot works.

Why it matters in your process

Every kilogram of feed you put in has an oxygen demand behind it, and the crash comes at 4 a.m. in August, at the bottom, where the aerator never reached. Ultrafine bubbles persist far longer than coarse bubbles, so oxygen reaches the whole water column and holds against demand, and stocking density stops being an oxygen decision.

Get a sized proposalEstimate my ROI
>30 mg/L
Dissolved oxygen demonstrated
(Well past air saturation · in our deployments and in published research)
70–83%
Ammonia removed
(Within 45 minutes · published research)
Peak feed
Sizing basis, not pond volume
(How the calculator and your proposal size the plant)
The problem

Oxygen demand peaks exactly when the water holds the least

Every kilogram of feed carries an oxygen demand: the fish that eat it, the bacteria that break down what they leave, the sediment that collects the rest. That demand peaks when solubility is lowest: warm water, dense stock, the hours before dawn when photosynthesis has stopped and respiration has not. A surface aerator fixes the top metre and leaves the bottom to run out. Once the sediment goes anoxic it releases ammonia and phosphorus back into the water you paid to keep clean, and low-oxygen opportunists such as Vibrio and Aeromonas find their niche.

The solution

Size the oxygen to the feed. Deliver it where the demand is.

We size the oxygen plant on your feed rate, not your pond volume, because feed is what sets the demand. Ultrafine bubbles persist far longer than coarse bubbles, so dissolved oxygen holds through the whole water column and into the sediment, against the load. Nitrifiers keep working: in published research, ultrafine-bubble oxygenation removed 70–83% of ammonia within 45 minutes. Low-oxygen opportunists lose their niche, and the muck stops releasing what you paid to remove. Oxygen is not a veterinary program. It lets the one you run work as designed.

Key benefits

Lower disease pressure

Vibrio and Aeromonas are opportunists of low-oxygen water. When dissolved oxygen holds all the way to the bottom, they lose the condition they exploit. It lowers pressure; it does not replace your health program.

Stocking density stops being an oxygen decision

Dissolved oxygen is the cap on how much biomass a pond or tank will carry, and it is the cap that fails first on a warm night. When the oxygen plant is sized off feed rate and the bubbles hold DO through the column, the density question moves to feed, filtration and market, where it belongs.

Water that stays clean between changes

An aerobic sediment layer keeps ammonia and phosphorus bound instead of releasing them back into the water, and gives nitrifying bacteria the oxygen they need to keep up. The direction is fewer water changes and less sludge to haul for the same water quality; the size of it depends on your feed load and your system.

What you're buying

An oxygen plant sized on your feed, installed on your water

One injection skid serves one production unit: a pond, a raceway or a tank. The proposal gives the exact model, power and materials for your site.

  • HardwareTitanium-core inline injector sized to your line, a PSA oxygen concentrator matched to it, and an optical dissolved-oxygen meter to read the result.
  • InstallTies into existing piping in 1–3 days; hours of interruption on the treated line, not days.
  • Lead time4–6 weeks from down payment to hardware on site.
  • PowerA dedicated GFCI-protected circuit, commonly about 220 V / 30 A (exact spec in the proposal).
  • Warranty3 years on non-moving parts (piping, injectors, cavitators); 1 year on moving parts (pump, oxygen generator).
  • MaintenanceInjectors and cavitators have no moving parts; pumps and oxygen generators are serviced every six months.
  • Ways to buyDirect from Kairospace, through a dealer near you (where to buy), or lease-to-own (3–4 month terms, lease fees credited toward the purchase).
  • Proof firstA pilot with a control zone: one pond or tank treated, a comparable one left alone. Pilot fees can credit toward the full system, up to 100% on structured trials. How a pilot works.
Get a sized proposalWhatsApp an engineerAn engineer replies within 48 hours, with a proposal or with the questions we need to write one.
Buyer questions

What buyers in aquaculture ask before a pilot

How is the system sized?

Off your feed rate, not your pond volume, because feed is what sets the oxygen demand. The plant is sized on peak feed rather than the cycle average, since feeding concentrates in the last weeks of a grow-out and the plant has to survive that day. The aquaculture calculator runs the same chain on your own density, grow-out length and conversion ratio.

What does a kilogram of oxygen cost me, against paddlewheels or liquid oxygen?

The calculator compares energy, kilogram for kilogram. It turns your feed into the kilograms of oxygen your stock needs on the peak day, sizes the injector, oxygen concentrator and circulation pump for the share you choose to supply, and charges that plant's electricity, the pump's electricity and service against the electricity your paddlewheels, aspirators or blowers burn today (nameplate horsepower, hours a day and your own rate per kWh). It never credits more aeration saving than the share of peak demand the plant actually supplies. It does not model liquid oxygen: LOX is a delivered price per kilogram plus tank rental, and that price is yours, not ours. Send us a recent LOX invoice and the proposal sets the two side by side. The calculator shows indicative list pricing; the proposal is the number you buy against.

Does it replace my aerators?

Not by default. The calculator asks what share of peak oxygen demand the system supplies and caps the aeration saving at that share, so at a modest share your paddlewheels keep doing most of the lifting. Past a point you are no longer supplementing your aeration, you are replacing it: a real engineering job, scoped in the proposal, not on a slider.

Does it work in ponds and in RAS?

The sizing handles both, with one difference: ponds carry sediment and plankton respiration on top of the animals, while a RAS tank is almost all fish. In a pond, oxygen that reaches the bottom keeps the sediment aerobic, so it stops releasing ammonia and phosphorus back into the water. In RAS, holding dissolved oxygen through the biofilter keeps the nitrifiers working at load; in published research, oxygen ultrafine bubbles removed 70–83% of ammonia within 45 minutes.

Can it run in saltwater or brackish water?

The injector core is titanium in every size, the gaskets are Viton, and the dissolved-oxygen meter has a titanium-alloy body. Piping is chosen from your water chemistry; the datasheet lists PVC Sch 40/80 or 316 stainless steel. We do not publish a salinity rating, so tell us your salinity and source (seawater, brackish well, recirculating salt system) and the proposal states the wetted materials for it, pump included, or tells you if the combination does not fit.

What about power, and backup during an outage?

The system needs a dedicated GFCI-protected circuit, commonly about 220 V / 30 A; the exact spec is in your proposal. Backup, alarms and a failure plan are specified in the proposal too, and they become part of the design once the system is carrying your oxygen demand rather than supplementing your aerators. Nothing on this page sizes standby power.

Who services it in Latin America?

Kairospace has an office in Mendoza, Argentina, and you can message an engineer on WhatsApp at +54 9 261 216-0527. Injectors have no moving parts; pumps and oxygen generators are serviced every six months, and the warranty is 3 years on non-moving parts and 1 year on moving parts. Tell us where the farm is, and the proposal says how installation and service are arranged for your site.

What do we measure on a pilot?

Dissolved oxygen through the water column, including at the bottom where the pre-dawn crash happens, alongside pH and the KPIs your farm is judged on, in a treated unit against an untreated one. We capture the baseline before treatment starts and review the readings with you at agreed checkpoints. You get a written results report, baseline against treated, with the economics, and if the difference isn't there, you stop and keep the data. How a pilot works.

Research

What published research reports

Figures are from published studies unless marked KST field data. Results depend on your water, so each one is tested on a pilot before it is a promise.

Your pond bottom is releasing what you paid to remove
The problem: Anoxic sludge at the bottom of a pond releases ammonia and phosphorus back into the water, feeding algae and stressing stock even after external inputs are under control. Waters et al., 2022
What the research reports: In published work, ultrafine bubbles delivered to the sediment layer re-oxygenated it and supported the aerobic bacteria that break down organic muck; phosphorus release from the sediment fell sharply once the layer went aerobic. An aerobic sediment also stops feeding the next algal bloom with the nutrient pulse it used to release. Our injectors deliver oxygen to that depth; how far your pond follows the studies depends on its sediment and load, which a pilot measures.
Yu et al., 2019Zhang et al., 2020Zhang et al., 2018
Ammonia is building faster than your biofilter removes it
The problem: Ammonia and nitrite are among the top killers in recirculating aquaculture systems (RAS). Nitrifying bacteria are aerobes; at high stocking density the biofilter runs out of oxygen before it runs out of surface.
What the research reports: In published work, oxygen ultrafine bubbles kept nitrifiers supplied and removed 70–83% of ammonia within 45 minutes. Our injectors hold dissolved oxygen through the biofilter and the tank, so the nitrifying population you already have keeps working at load.
Subhan et al., 2021Yaparatne et al., 2024
Off-flavors are making your fish hard to sell
The problem: Blue-green algae produce geosmin and MIB, the compounds behind an "earthy" taste and smell. Once they are in the flesh, the harvest waits through a purging cycle or goes at a discount.
What the research reports: In published work, oxygen ultrafine bubbles degraded geosmin and MIB through oxidation at the bubble interface, removing a meaningful share of each, and a water column that stays aerobic gives the cyanobacteria that produce them less room. It shortens the purging problem; it does not remove it.
Soyluoglu et al., 2022Foudas et al., 2023