More of the stock survives, and what survives grows.
In a hatchery raceway or a grow-out pond, survival and growth ride on the oxygen the water can carry, and a stocked system spends it fastest overnight, when nothing is putting it back. Follow one night down the column, and watch where the oxygen goes.
Stocking density is how many animals a water carries, and a farm carries far more than a pond ever would. Feed goes in through the day, the animals and the bacteria working through their waste both draw dissolved oxygen, the oxygen held in the water itself, and by dusk the water is spending it faster than a diffuser can put it back.
before dawn, the oxygen spent
the same raceway, oxygen held to the floor
Through the night there is no photosynthesis to add oxygen back, only respiration taking it away, so dissolved oxygen falls all night and bottoms just before dawn. The animals crowd toward the surface where the last of it is, and a grower can lose a season in one quiet morning. The dark layer that gathers along the floor is the oxygen debt, the water that runs short first.
Nanobubble oxygenation makes bubbles too small to rise, so instead of bursting at the surface within seconds they stay suspended, carrying oxygen through the whole column and down to the floor where the shortage starts. The debt recedes, the water clears, and the school comes back down into open water.
With oxygen carried the full depth around the clock, the pre-dawn low never reaches the level that stresses the stock, feeding stays efficient, and the water stops setting the ceiling on how many animals it can hold.
Farmed water fails from the bottom up. The animals, the uneaten feed, and the bacteria breaking down waste all draw dissolved oxygen, the oxygen held in the water itself, and the sediment runs short of it first. Through the night there is no photosynthesis to replace what respiration takes, so the oxygen falls until just before dawn, which is why die-offs arrive in the morning and not at noon.
Nanobubble oxygenation, oxygen in bubbles small enough to stay suspended instead of rising and bursting, carries dissolved oxygen through the whole column and down to the floor where the shortage starts, and adds nothing else. The technology pages lay the mechanism out in plain English, and how we measure shows the standard every claim on this site is held to.
| hour | dissolved oxygen (mg/L) |
|---|---|
| 0 | 7.2 |
| 3 | 5.4 |
| 5 | 4.2 |
| 7 | 5.6 |
| 10 | 8.4 |
| 13 | 11.2 |
| 16 | 12.6 |
| 19 | 10.8 |
| 21 | 9.0 |
| 24 | 7.2 |
These findings describe nanobubble oxygenation as a mechanism, not an Alchemal unit. Our own installations publish their own record as case files.
A crash before dawn, a black bottom by mid-cycle, a feed bill that climbs while growth stalls. In grow-out the margin lives in the overnight oxygen, and one hot night can take a season's work. You want numbers, not adjectives, which suits us.
In a hatchery the value per animal is highest and the tolerance for a bad night is lowest. Larvae and fingerlings feel a swing in oxygen before anything else does, and a few hours of low water can undo weeks of careful work.
On flow-through raceways the water arrives rich and leaves used, and the last pass runs the tightest margin. Carrying capacity is set at the lowest-oxygen point, and trout or catfish crowd it whenever a warm spell thins the source.
In a recirculating system the margins are tight and the biology is unforgiving. When the biofilter runs short of oxygen, ammonia creeps up and the whole loop feels it, and a water change spends the heated, conditioned water the design exists to keep.
The N-Series is one platform in four sizes, chosen by the volume of water it has to oxygenate rather than by the kind of farm. A small hatchery raceway or a nursery tank sits in the range the N1 covers, to about a quarter acre of surface; a grow-out pond up to a few acre-feet, the volume of water one acre holds at one foot deep, sits in the N2 range. Larger ponds and multi-pond sites step up from there. An assessment sizes the unit to the water and where it installs.
1
Describe the problems you are facing, and we work with you to find out whether Alchemal is the right solution for your water.
How the assessment works →2
The N-Series unit goes in at your water and gets to work: oxygen through the whole column, and sensors that let you watch the response.
The N-Series line →3
We stay with you to keep the water improving, the unit running well, and the results where you want them.
What Stewardship covers →Describe what you are seeing, and a specialist will help you determine whether Alchemal can help you fix it, before any commitment.