pH Shock Symptoms in Fish

Keeping an aquarium requires making sure you maintain the water's pH level within the requirements of the fish you are keeping. Monitor your water balance, hardness and pH level, and if you need to alter your pH, make sure you do so slowly in order to prevent drastic changes, which would put your fish at risk.

  1. What Is pH Shock Syndrome?

    • Caused by rapid changes to a body of water's pH level within a short period of time, pH shock syndrome can be fatal to aquarium fish. The common causes of rapid pH changes may include large water changes and adding the wrong or too much chemical to the water. When you get new fish, the water in the bag may have a different pH than your aquarium's water has, especially if the fish have been in the bag for several hours. If you do not acclimate the fish to the new water, they may suffer pH shock.

    Signs of pH Shock

    • Suffering from pH shock, fish may become lethargic, imbalanced and listless. They may stop eating, and you may notice heavy breathing. Some fish may remain fairly motionless on the bottom of the aquarium; others may produce excess slime, making them look a little off-white, which is much easier to see in darker fish. The dorsal fin may drop and appear floppy. If the pH level isn't corrected, the fish will usually die within a few days.

    Monitor the pH Level

    • It's important to monitor the pH and KH or carbonate hardness levels of your aquarium to avoid acute pH shock. Purchase a digital monitor or paper strips so you can regularly test your aquarium water. You want to make sure you test before and after partial water changes, as well as before and after you have to add chemicals. This will help you detect any drastic changes to the pH quickly so you can make corrections before your fish are affected.

    Treat pH Shock

    • The best way to treat pH shock is to treat the water conservatively. Add pH adjustment chemicals to the water after you've tried less drastic measures. You want to make sure that the pH level is adjusted slowly, or you can worsen the shock to your fish. You may want to start with a partial water change, to see if the pH and KH will adjust naturally. Otherwise, if the hardness is too low, you can add a few drops of potassium bicarbonate or sodium bicarbonate every hour to see if the pH has adjusted and the KH has increased. If the hardness is too high, you may want to consider removing the decor because they may be releasing chemicals or gases into the water, which could be affecting the pH level.