Chances are you got your betta fish at a pet store of some kind. If you had the typical experience, you got a person that told you nothing about the water requirements for your betta or anything else about betta fish care. They may or may not have told you that you needed to change the water, but gave you no guidance. Actually, when you got home and got a good smell of the water your betta was in, you decided to change the water out.

You may be inclined to think that any water will do. Most clean water looks, smells and tastes the same, unless it came out of a toilet bowl or something like that, right? Seriously though, different sources of water produce water that has many different characteristics. There are many invisible, and hard to distinguish factors that can have a bad effect on your betta. These invisible things could actually kill your betta.

Here are a couple of water parameters that you should keep in mind when taking care of your betta:

Water pH.

Without getting into a chemistry conversation, pH is a measure of the acidity of the water. If you think about what acid does, you’ll understand the importance of keeping an eye on this measure. The range goes from 0-14 and the lower the number, the higher the acidity. A pH of 7 is a neutral reading, meaning that the water is neither acidic nor basic.

The thing with the pH level of water, is that it’s tied closely to the source of the water.

Typically speaking, if your water comes from an underground source and has been seeped through lots of different rocks, it probably has a lot of dissolved minerals in it. Water with a lot of minerals disolved in it
is called “hard water”. Water from lakes or ponds, where maybe there was a lot of decaying materials etc. usually has more acidity to it but is called “soft water.” In some places, the rain water collects so many chemicals as it makes its way through the atmosphere that by the time it reaches the ground it’s called “acid rain.”

Lots of mineral in suspension = hard water = high pH. The opposite is also true, less minerals = soft water = low pH.

The only way to tell if your water has high or low pH is to measure it with a pH test kit. The test kits are cheap, but you must have one in order to test the acidity of the water. Most water in the US will test between 6-8, but hardly any water will test at the magical 7 without being treated.

Most tropical fish, such as bettas need water that has a neutral pH, meaning the water should test at a 7. To adjust the pH of the water, you need to add “pH up” or “pH down” depending on the case to the water, until it tests at a 7.


Any adjustments to the pH must be done gradually. Bettas, like most fish, are very sensitive to sudden fluctuations in their water environment. Only add a few drops at a time of either solution to keep the change as gradual as possible.

Water Temperature

Fish are very sensitive to the temperature of their water.

Tropical fish like water temperatures between 75F and 82F. You may need to get a heater to keep the water within that temperature range, specially if you have a large tank. When it comes to water heaters for your fish tank, you really do get what you pay for, so get the best quality heater that you can afford. You do not need a heater if your tank is smaller than 5 gallons since you may end up cooking your fish.

Regardless of the size of your tank, water temperature, is something that you can’t see, so you’ll need to have a thermometer for your tank. Just use one of those that stick to the side of the tank and you should be fine.