Have you ever jumped head first into a lake or pool without testing the water? The initial shock can be easier to handle than wading in gradually, but it doesn’t work the same way with aquarium fish. When you bring home a new fish to add to your bowl or tank, its important to let it fully acclimate to the new surroundings.
Step 1: Test Your Water Parameters
Testing is especially important if you’ve recently set up your tank. Record the temperature and pH level of your aquarium water well as the water in your transport bag or container. A pH test determines acidity, which is directly affected by mineral content. Betas, in particular, prefer soft water with a slightly acidic pH between 6.0 and 7.0. You may also want to check ammonia, nitrate and nitrite levels.
Step 2: Float the Bag or Container
Warm-water species are fairly adaptable to gradual fluctuation, but sudden temperature changes can be fatal to your fish. If your transport water is even slightly high or low, float the bag or container directly on the surface of your aquarium water. The temperatures should line up within about 30 minutes.
Step 3: Exchange Water
Use a binder clip or clothespin to secure the float to the inner rim of your tank. Then, remove and discard about one tablespoon of water from your bag and replace it with an equal amount of aquarium water. Continue to repeat this process in 10-minute intervals, preferably over the course of an hour. This slowly eases your fish into the new environment. It also reduces the risk of transferring any hidden contaminants that may have hitchhiked from the pet store.
Acclimation is extremely stressful for any fish, so be sure to leave plenty of time. Whether you’re keeping betas or mollies, do some research beforehand. In general, consistency is key to maintaining the ideal environment.