maadi
New Member
My tank is about 120 gallons and has been established for several years. Two weeks ago I did 2 water changes of about 25%, using Seachem Prime to treat the tap water. Last week, I did another 25% with Prime, and also added some Seachem Pristine and Stability, which I occasionally add with water changes. I remember shaking the bottle of Prime before adding it but am not so sure I shook the other two bottles first, as I usually do. It was the bottom of the Prime bottle. Expiration dates on the bottles are 2023-2024. I did forget to plug the water heaters back in, but the evening wasn't cold.
The next morning (just as I was about to go out of town!), over half of the fish had died. I quickly removed the dead ones and did another 25% water change, using Seachem Safe (about 1/8 teaspoon), because I was afraid to use anything I'd just used the day before. A couple of fish floating at the top suddenly swam away when I tried to remove them, and have survived the week. Malaysian trumpet snails appear unaffected.
After finding the dead fish, I was scared and in a rush to change the water as quickly as possible, so I didn't test the water. One week later, before the latest water change, ammonia was <0.25, pH about 8.3, nitrate about 5, nitrite 0. Then I did another 25% water change with Seachem Safe.
What went wrong?
Did my possible failure to shake the Pristine or Stability bottles add something toxic? Did the water change possibly stir up methane or other toxic gases in the substrate? Did the tap water possibly contain higher than normal chemicals? Temperature change? Something else entirely?
I'm afraid to kill off the surviving fish with each water change.
The next morning (just as I was about to go out of town!), over half of the fish had died. I quickly removed the dead ones and did another 25% water change, using Seachem Safe (about 1/8 teaspoon), because I was afraid to use anything I'd just used the day before. A couple of fish floating at the top suddenly swam away when I tried to remove them, and have survived the week. Malaysian trumpet snails appear unaffected.
After finding the dead fish, I was scared and in a rush to change the water as quickly as possible, so I didn't test the water. One week later, before the latest water change, ammonia was <0.25, pH about 8.3, nitrate about 5, nitrite 0. Then I did another 25% water change with Seachem Safe.
What went wrong?
Did my possible failure to shake the Pristine or Stability bottles add something toxic? Did the water change possibly stir up methane or other toxic gases in the substrate? Did the tap water possibly contain higher than normal chemicals? Temperature change? Something else entirely?
I'm afraid to kill off the surviving fish with each water change.