What would cause a goldfish tank to drop below 6.0 in pH?
I have a 40 gal goldfish tank. Today 2 of the 7 fish were dead. I checked the temp (65F) and the pH. The pH was off the scale at less than 6.0. What could cause such a large drop in pH?
The tank was set up 6 months ago. I checked the pH through the cycling and it was stable at around 7.2. Haven’t checked pH in the last 4 months.
Everything I put in the tank (gravel, Malaysian driftwood) was from a pet supply store so I don’t think that is the problem.
I checked the pH twice and compared it to a control sample. Sure enough the measurement seems reliable.
Measured the Ammonia and it is way up at 5ppm. It’s like the biological filter just stopped working. There’s 20-30 inches of fish in this 40 gal tank so I don’t think it’s overstocking.
Doing water changes to try to bring it back in….
I’ve only been doing 25% water changes monthly. Looks like I’ll have to up that.
Tagged with: 4 months • ammonia • biological filter • driftwood • fish • gal tank • goldfish • goldfish tank • gravel • measurement • pet supply store • water changes
Filed under: Pet Supplies & Pet Care
Like this post? Subscribe to my RSS feed and get loads more!
It is your drift wood that is causing the problem. Drift wood and peats naturally lower the PH of water while sea shells naturally increase it. However goldfish are fine in a 6 PH as long as it is a stable one. When doing a water change how much water are your changing out? More than 25% will increase then lower the ph due to the drift wood which does not make for a stable PH. Have you checked your ammonia and nitrites and are you sticking to the weekly water change? These are musts for goldies. It is your drift wood hun. Either you need to do less water change to keep the ph stable or remove the drift wood or add a few seashells into the filter to balance the PH any way will work. Your Ammonia is off the chart at 5 you need to test your tap water since most water companies are now using ammonia to treat water instead of chloramates. Also if you use any ammonia lock type water conditioners or right out this will also alter the ammonia reading. More than likely it is the ammonia spike that killed your fish.
Your tank is by no means over stocked. You have to start the 25% weekly not and never monthly water change. Sorry all fish should be on this schedule with the exception of salt water.
Good like and if you have additional questions feel free to email or repost.
well the thing is those type of fish release allot of ammonia and are very dirty also the fish tank was to small for the 7 goldfish
so the fish are the ones to be blamed you should get different type of fish or a bigger fish tank
hope i could helped you
i had exactly the same problem, my control samples were perfect but my ph kept crashing. Do you do a 25% change each week? are there any hidden ‘nooks and crannies’ in your tank that may be collecting dirt? do you thoroughly vacuum the gravel when you do a water change? even though i was doing 25% weekly change, i found a few things that i was neglecting (hidden ‘dirty’ spots and i wasn’t vacuuming all round the edges & corners and right to the bottom of the gravel) I learnt by trial and error, and a few lost orandas. don’t put anything like ‘PH Up’ in the water, that’s only a quick fix and it will cause the ph to rise and fall rapidly, resulting in more fish loss. The best solution I found was to add some well rinsed crushed coral to the gravel (total 3 cups, a cup at a time, wait 2 days then test) in my 55 gallon tank. I’ve had no ph problems for months now, a steady 7.4.
i hope this info helps you, and i hope you don’t lose any more fish
It is your driftwood.
the rule for the goldfish is 10 gallon per fish you maybe overstocked it