Shipping, Receiving, Acclimation and Introduction

An animal arriving from a shop, a breeder or another system goes from one set of water conditions to another: temperature, salinity, pH, ammonia and light can all be different. Small differences are easy to absorb; large or sudden ones are a shock that stresses it, and a stressed animal is more likely to get sick.

Acclimation is the set of steps that brings the animal across without a sudden change. Have everything ready before it arrives: the place it's going, a container to acclimate it in, a meter and thermometer, a net and cup that belong to this animal, an air stone, a heater and ammonia neutraliser. Arrivals do best when they reach stable, mature water quickly. Avoid fine-mesh holding containers: the mesh can clog with biofilm, and the water inside runs out of oxygen without anyone seeing it.

In a sealed bag the animal uses oxygen and gives off carbon dioxide and ammonia. The carbon dioxide can't escape, so it lowers the pH. At a lower pH most of the ammonia is ammonium, the much less toxic form, and that's part of what lets animals survive a long trip.

Opening the bag lets the carbon dioxide out. The pH rises, and the ammonia shifts to its toxic form within minutes. That's why an animal never sits in an opened bag. The bag water and the animal are poured into the acclimation container, and an air stone and an ammonia neutraliser such as AmQuel go in immediately. The air stone puts oxygen back, but it also drives carbon dioxide off faster, which raises the pH; the neutraliser is what makes that safe. Warmth makes it worse: the animal's oxygen use and waste production roughly double with every 10 °C.

The bag water and the animal are poured together into the acclimation container. The packed water has to come with the animal: it's the water the animal is adjusted to, and everything else is changed slowly from there. An air stone and an ammonia neutraliser such as AmQuel go in immediately, before anything else.

Then the temperature is adjusted slowly in the container with a heater. Only when the temperature matches does the drip begin, and the water for the drip is replaced in the system FIRST. The order matters because each step makes the next one safe: the neutraliser and air deal with the ammonia and oxygen, the heater deals with temperature, and the drip deals with salinity and pH.

A heater in the acclimation container brings the water slowly to the destination temperature while the air stone runs. A sudden change in temperature is a shock on its own, and warmer water speeds up the animal's oxygen use and waste production, which is one more reason the air stone and neutraliser are already in.

Check with a thermometer rather than by feel. When the temperature matches, measure the salinity, and the drip can begin.

Measure the water in the acclimation container and the destination water with the same meter, so the difference is real and not a difference between two meters. A difference of 1 ppt or less doesn't need acclimating: the animal can move on without a drip. A larger one is closed slowly with a drip: destination water drips into the animal's container until the salinity matches, often until the volume has doubled or tripled.

The drip water comes out of the destination system, so the same amount of matched saltwater goes into that system FIRST, before the drip starts (see Water you take out). The drip rate is set with a valve or a knot in the airline. A common rate is 2 to 4 drips a second for fish and 1 to 2 for invertebrates, which are more sensitive to salinity change. A drip isn't free: as destination water raises the pH, any ammonia left in the water becomes more toxic, so the drip runs in an aerated container with ammonia neutraliser in it.

When water is taken out of a system, an auto top-off refills it with fresh water, so the salinity drops. An acclimation drip can take several liters. Taking water out for acclimation means adding it FIRST: the same amount of matched saltwater goes in before any water comes out, and the salinity holds. Never the other way around.

Measure what goes in and what comes out with a graduated cup or bucket, not by eye.

Shipping water can carry ammonia, waste and pathogens from wherever the animal came from. It goes into the acclimation container with the animal, and that's where it stops: the water in the acclimation container never goes into a system or a rinse bucket, and it's thrown away when the animal has moved on. After the drip, the animal passes through two rinse buckets of destination water, so as little of the old water as possible comes with it (Module 23).

Catch a fish with the net under water and carry it in a cup. A fish lifted out of the water in a net can tear its fins and damage its slime coat; long-finned fish are the most at risk.

A fish that's gasping, on its side or barely moving is often being harmed by the bag water itself, and leaving it in the bag keeps it there. Pour it and its water into the acclimation container at once, with the air stone and ammonia neutraliser in immediately. Then adjust the temperature slowly with the heater, and begin the drip. Keep the lights low and leave it alone; checking on it again and again adds stress.

Then watch it. A new arrival that keeps showing symptoms, such as fast breathing, gill flaring or fin damage, needs to be assessed and treated (Module 30).

Invertebrates handle salinity change worse than fish, so they're acclimated more slowly. An anemone is lifted by hand with its foot supported; pulling it off a surface or catching it in a net can tear it. Pump intakes are covered before it goes in (Module 22), because anemones move. Each species has a preferred spot: S. haddoni on the sand in gentle flow, S. gigantea and H. magnifica in bright light and strong flow, and H. magnifica climbs rather than sitting on the sand. A new anemone may wander for weeks before it settles, which isn't a problem on its own.

Clams and corals arrive after time in the dark and may have been kept under weaker light. Too much light too fast can bleach them. A clam is started low in the system and moved up toward its final spot over about two weeks. Corals are covered in Module 27 and clams in Module 28.

Ship only healthy animals. Fish are usually not fed for a day or two before, so there's less waste in the bag. The bag is filled about one third with water and two thirds with pure oxygen, because oxygen is what runs out first. Two bags, one inside the other, mean a single leak isn't the end, and taping or rounding the corners keeps small fish from getting trapped.

The bags go into an insulated foam box inside a cardboard box, packed so nothing moves. In cold weather a heat pack, and in hot weather a cold pack, is fixed to the box and never touches a bag. The box is labeled as live animals, this side up, and shipped to arrive the next day, with the receiver told when to expect it.

Keep the lights off or low for the first hours after the animal goes in. Add animals one at a time and watch: whether it eats, whether it's being chased, and whether it's harming anything (Module 24). New animals usually go through quarantine first (Module 23).

When an arrival goes wrong, trace the step that caused it: an animal left sitting in its bag, no air stone or neutraliser, a drip started before the temperature matched, water taken out of the system without being added first, container water that went into a rinse bucket or a system, or a fish lifted in a net.