How to Change your Tank Water without harming your Betta Fish

Just because your tank looks clean doesn’t mean the water is healthy. High ammonia and nitrate levels caused by waste aren’t
visible but can seriously stress out your Betta.

Keeping healthy water conditions in your Betta’s tank is THE most important thing you can do to provide long-term health and happiness.

If you keep your Betta in an unfiltered bowl then you should change30-50% of the water every week – the smaller the bowl the more water you should change.

If your Betta lives in a filtered tank then you only need to change out about 20% of the water each week.

Now, you don’t simply dump out a bunch of water and dump new tap water in, right? Of course not, that would seriously stress out your Betta Fish.

So here’s how to change water in your tank:

  • Have a clean spare tank, jug or container for the new water
  • Fill the spare tank the day before allowing it to reach room temperature
  • Add some water conditioner to the spare tank to help remove the chlorine and other chemicals that unfortunately exist in our tap water
  • Remember how much water your need to remove, then use a plastic hose or tube and siphon the water you need to remove into a bucket.
  • Try to siphon from the bottom of the tank where the food and waste collects. siphon
  • If you are not sure how to siphon water simply put one end of the hose in the tank and the other lower than the tank near the bucket. Give the hose a very quick suck to get water moving but obviously pull it out sooner than later so water winds up in your mouth. This should start the water siphoning and get it pouring into the bucket. Then simply pull the tube/hose out of the tank when enough water has been removed.
  • Now you can either clean the hose and siphon the fresh water in, or dump it in very slowly. The key is to not stress out your fish. So be very gentle getting the new water into the tank.

If for some reason your tank is disgusting and literally needs to be
scrubbed then you need to remove your Betta, but save enough of the
dirty water so your Betta can survive in a bowl while you clean the

Thoroughly scrub your tank and all elements (rocks, plants, etc),
dumping out the old nasty water.

The trickiest part is getting your Betta (who is still swimming in a
bowl of the old water) acclimated with the new water and the clean

The trick is to slowly add the new water to the small bowl over the
course of several hours, removing some ‘old’ water each time if you
have to make room.

Once there is a enough new water in the small bowl and your Betta
seems ok, then fill the tank with the rest of the new water. Then
either use a net to transfer your Betta back into its tank, or dump
the mix of old and new water plus your Betta from the small tank
into the large one.

Well, congrats as you’ve finished reading the Betta Answers mini
course. Hopefully you’ve found these emails helpful to the care of
your Betta Fish. Feel free to share this tips with friends and

If you have any questions or things you’d like to read more about
then let us know via our Contact Us form.