Drip acclimation is the most gradual, and therefore the safest, method of acclimating fish to new water with potentially different parameters (for more on these parameters, see our WATER CHEMISTRY page). 


  • Air line tubing
  • Air line gang valve
    • OR, if you don't have one of these, you can use bull clips, or other small clips to clamp the tubing and restrict the water flow
  • A clean, rinsed bucket or vase with an open neck
    • This should be an appropriate size to hold all of the water that the fish comes home in while leaving the fish still covered in water.
      • This is only required if your fish came home in a bag
      • If they came home in a cup, it may be best to simply acclimate in that cup.
  • Turkey baster
  • Scissors
  • Tape (optional/as needed)



If your fish came home in a bag, you will need to transfer him/her into your bucket to begin with.  Sit the bag on the bottom of the bucket and roll down the top edge of the bag to within a couple of inches of the water level in the bag. Then, holding the top edge of the bag so that it doesn't collapse, grasp one bottom corner and lift it up to gently pour the water and fish into the bucket.

  • Do not attempt to pour the fish/water into the bucket from any height. The waterfall created could slam your fish into the bottom or side of the bucket, injuring him.

Situate the bucket/vase/cup containing your fish and his pet store water on a stable surface near his new tank so that the water level in the bucket is below that of the tank.

  • The water flowing from the new tank into the acclimation bucket/container will be driven only by gravity, so you must ensure that the tank's water level is above that of the bucket to facilitate flow.
3. Cut a length of air line tubing long enough to reach from inside your acclimation bucket/cup into the new tank and about 4-5 inches below the water' s surface.

If you are have an air line valve, cut your length of air line tubing at its middle and connect each end to the valve. Open the valve completely.

  • If you will be using clips to restrict water flow instead of a valve, do not cut the tubing. The clips will be applied later.
5. Open the lid of the fish's new tank and insert one end of the air line tubing down 4-5 inches below the water level. Tape the airline tubing to the outside of your tank to secure it, if needed, or hold it in place by closing the tank lid on it.
6. Watching the tube closely so as not to ingest any water, take the other end of the air line tubing in your mouth and suck very gently to start water flow, drawing it down the tube to some point beyond the air line valve. This flow can be paused by placing your finger over the end of the tube.

Screw the air line valve almost completely closed until water is coming out of the air line tube at 1-2 drips per second. Place the end of the air line into your acclimation bucket so that it hangs above the surface. Secure with tape if necessary.

  • If you will be using a bull clip or another type of clamp, fold the the air line tube in half and apply the clamp to this fold. Adjust the degree of the fold and the placement of the clamp on it until water flow is restricted to 1-2 drips/second as outlined above.
  • If you are acclimating your betta in a cup, slow the drip rate down to MAX 1 drip per 2 seconds to begin with. In such a small water volume as a cup, each drip accounts for a larger percentage of the water volume, and the transition to the new, dripped water must proceed slowly.
  • If your betta is being acclimated in a cup, they must be monitored to be sure they don't jump out of the cup if the water level is within a few inches of the top the cup/container.

Once the water volume has doubled (ie: an amount equal to the water the fish originally came home in has been dripped into your acclimation container), use your turkey baster to remove and discard half of the water in your acclimation container.

  • It should not take less than 30 minutes for the water volume to double. If it does, you are going too fast.
  • At this point, the water in the acclimation container is 1/2 old pet store water and 1/2 new tank water.

Increase the drip rate to 2-4 drips per second and allow the water volume in the acclimation container to double again.

  • This second stage should also take no less than 30 minutes
  • At this point, the water in the acclimation container is 1/4 old pet store water and 3/4 new tank water.
10. At this point, you can prepare to release your fish. Using your turkey baster, remove much of the water from your acclimation container, leaving enough to gently pour your fish into the tank without leaving him out of water while pouring.