Reef Flourish

A working day over a reef begins before the vessel does. Satellite sea-surface products and the site's own instruments say where accumulated stress is highest this week; the tide table says when the flat will be shallowest and stillest; last week's profiles say which part of the lagoon stopped mixing.

Then the boat goes to the water that scored worst, and the first thing it does is measure rather than treat.

What a working day actually consists of

1. Profile first Temperature, dissolved oxygen, pH and turbidity through the column at fixed stations. On a reef flat that means shallow work at several points rather than one cast, because a lagoon is not uniform and one cast cannot describe it.
2. Break the cap, if there is one Where warm surface water is sitting on cooler water and refusing to mix, the vessel works that boundary. Where no cap exists, this step is skipped and the day's plan says so.
3. Oxygen through the column Water is drawn aboard, saturated inside the reactor and returned to the layer that needs it. Sub-micron gas does not rise and burst, so the cloud stays in suspension and keeps working through the surrounding water for hours after a pass — which is what lets a vessel-sized gas budget reach a lagoon-sized volume. Published aeration work reports the gas-transfer coefficient at roughly eleven times its conventional value for the same delivered volume; comparable studies report considerably smaller gains, and a hull is sized off the low end of that range rather than the top.
4. Clarity, taken in rather than dropped out Where bloom material or organic load is cutting the light, that water is drawn into the reactor and handed back clear. Nothing settles onto the reef. And where the site is under active heat stress, this step is left out entirely, for a reason that is pure reef biology.
5. Profile again, same stations The comparison that matters is the same points, same depths, same instruments, before and after. Both sets go to the institution holding the season's record as they are logged.

The rule over living coral is zero

Over live coral and over a nursery, the ozone dose is zero. Not the lowest setting this platform runs. Zero — every site, every season, with nothing left to a crew's judgement on a difficult afternoon.

The chemistry is why. In seawater ozone goes after bromide roughly eighty-three times more readily than chloride, and the hypobromite that comes out of it can carry on to bromate — a stable end product, which means it cannot be quenched afterwards and cannot be diluted into compliance. So the answer is not a tighter cap over your lagoon. Where a mission genuinely needs oxidation, the water is drawn away from the reef, treated inside a contained reactor and discharged clear of live habitat, against a standard applied at the outlet rather than to the sea around it.

Nothing is dosed into reef water, and no clay, modified clay or flocculant is dispensed onto a reef. Clarity comes from taking turbid water in and handing clear water back, which in a lagoon with limited exchange is the difference between a treatment and a deposit.

And the duty that gets suspended

During active heat stress the clarity work stops. Moderate turbidity shades a reef, so stripping it out inside a bleaching window would take away the one thing on that site currently working in the coral's favour. The oxygen duty carries the water until the accumulation comes off the record.

Reef managers recognise that rule immediately, and they should. It is the point where a treatment plan stops being an equipment schedule and starts being reef biology.

What is published, and where it was measured

Three records sit behind this platform. None was taken over coral.

The physics is published: sub-micron bubbles behave as a stable suspended phase rather than as something rising to burst, and the gas-transfer advantage over conventional aeration has been measured. NOAA's coastal science centres reported in 2018 that an ozone nanobubble system cleared algae from an eight-acre Florida pond inside two days, with reoxygenation held and no apparent harm to aquatic life. A 2020 NCCOS-affiliated ballast-water evaluation found no statistically significant adverse residual toxicity in receiving water. Both used other operators' equipment.

Alarivean's own field record is a Florida DEP permit, FLOA00062, granted in September 2024 for red tide trial work and independently logged by the Sarasota Bay Estuary Programme and START. The estuary programme backed the application technically, accepted none of the funding, and wants to be the body taking the measurements when open-water evidence is produced. We want them holding those instruments too. No open-water result has been published for this class of treatment — ours or anyone's — and the published record runs to pond scale and ballast-tank scale.

Which is why a first reef programme is written as a calibration exercise: a bounded area, pass and fail parameters agreed before the vessel arrives, an independent institution taking the readings, and pricing that matches. A published reef result will come out of a programme built that way or it will not come at all.