How to acclimate shrimp

The short answer

Shrimp cope with a wide range of conditions and very poorly with fast change in them. A sudden swing in TDS or hardness disrupts molting, and the losses show up days later, long after the acclimation that caused them. That delay is why people blame the shrimp, the supplier or the tank when the real culprit was ten rushed minutes.

What you need

Step by step

1. Prepare the tank first

The tank should be cycled, planted and holding steady before shrimp arrive. Test TDS in your tank so you know the target. Dim the lights and turn off any strong flow near where you will work.

2. Float the sealed bag for about 15 minutes

This equalises temperature only. Keep the bag closed and clipped so it does not fill with room air or ammonia-laden water.

3. Move shrimp and bag water into a clean container

Use a small, clean, food-safe container or bucket that has never held soap or chemicals. Pour in the shrimp with their water; do not net them out yet.

4. Start a slow drip

Run airline tubing from your tank to the container, tied or clamped so water falls at about one to two drops per second. A loose knot in the tubing or a cheap airline valve works. Siphon start by sucking gently on the end, then let the tank water drip in.

5. Wait until the volume doubles, then again if you can

For Neocaridina that is usually 60 to 90 minutes, and for Caridina two to three hours. If you own a TDS meter, check both waters; the closer they are, the safer the move.

6. Net the shrimp and discard the bag water

Move the shrimp into the tank with a fine net. Do not add any water from the container or bag to the tank.

7. Leave them alone

Keep the lights low for the first day, do not chase them for a look, and hold off on water changes for a few days.

Neocaridina vs Caridina

Neocaridina are forgiving: an hour to ninety minutes of drip is usually plenty. Caridina move between two very different waters and tolerate almost no drift, so give them two to three hours and check TDS on both sides first. See Neocaridina vs Caridina for why the two need different water.

Mistakes that cost colonies

Pouring bag water into the tank. Net the shrimp out and discard it. Skipping the drip because the shrimp look fine. They always look fine; the damage is delayed. Acclimating into an unfinished tank. Fresh, uncycled water is where most early losses start. Copper. It overrides every rule here and shows up in some fish medications and snail treatments, so read the label before anything goes in.

Questions we get asked

How long should I acclimate shrimp?

Plan on one to two hours for Neocaridina and two to three hours for Caridina, dripping slowly enough that the container volume roughly doubles or triples. Faster is the mistake that costs colonies; the damage often shows up days later as failed molts.

Should I pour the bag water into my tank?

No. Net the shrimp out of the bag or container and discard the water. It can carry ammonia and chloramine-treated or differently mineralised water you do not want in your tank.

Do I need to float the bag?

Floating the sealed bag for about fifteen minutes lets the temperature equalise before you open it. It does not replace drip acclimation, which handles the change in water chemistry.

Why do shrimp die days after acclimation?

Shrimp react to the rate of change in TDS and hardness. A fast swing disrupts molting, and the losses appear days later, long after the acclimation that caused them. A TDS meter on both waters tells you how big the gap is.

Do Caridina need a slower acclimation than Neocaridina?

Yes. Caridina usually move between two quite different waters, soft RO-based water and whatever they were shipped in, and they tolerate very little drift, so give them the longer end of the range and check TDS on both sides first.

Keep reading