Today has been very eventful for my fish. They have had peat introduced to their community tank both in the filter and partially dissolved in the replacement water during the water change. I was worried about stressing or shocking them but decided drastic action was required.
I calibrated and replaced the batteries in my digital pH meter yesterday as I wasn’t altogether happy with the test strips and how vague the readings were. I was shocked to discover the pH of our tap water was above 8. It used to be around 7. I then tested all my tanks, the breeding tank read the highest at almost 9 with the water change tank coming close to the tap pH around 8. The larger empty tank was higher too. The community tank that is occupied by all of my fish just now and overcrowded was at 7.1 yesterday but had climbed 0.4 up to 7.5 by today. This could have put my fish into shock and the Tetras did appear to be suffering. They were a much paler in colour than usual.
I took action to try and bring the pH down a little. I added peat to a filter and placed it in the tank but there was no immediate change after several hours so I then crushed the peat balls into the water change tank to bring it down in pH, measuring it constantly until I got to 7.1, then I did a water change that resulted in lowering the pH by 0.2 back down to 7.3. The Tetras began to look a little healthier almost immediately but having just measured the pH again tonight it appears to have climbed by 0.1 now up to 7.4. This will most likely be due to the buffers naturally present in the water.
I believe that the very high KH reading in the breeding tank was possibly down to boiling the water first. According to the test strips our tap water is soft with lower GH and KH readings but I have already decided the test strips cannot be trusted and are unreliable as they did not pick up on the pH fluctuations the same way my digital meter did. If I am to have any faith in the readings I got then the tap water should be adequate for the Tetras and breeding them. Boiling the water certainly hasn’t helped my breeding tank parameters at all. It just sky rocketed the KH and pH readings.
Lowering the pH in the community tank will be tricky as it is occupied and the shock if I get it wrong could prove fatal to my fish. It will need to be done gradually over time using water changes twice weekly and only lowering it by 0.1 at a time. The other tanks should be easier to adjust but will need to match the community tanks parameters very closely when introducing the fish to them and the cycling of the tank will also bring about fluctuations.
The good news is the higher pH is perfect for hatching my Brine shrimp which is happily bubbling away in a plastic drinks bottle submerged in empty larger tank. I adjusted the heater to raise the temperature and it is directly under the lights which have been left on throughout the night recently to stimulate the aquatic plant growth. I rinsed the filter from the community tank earlier in the empty tank to make sure some of the bacteria needed for cycling would be introduced. So hopefully I will be feeding my fish live freshly hatched Brine shrimp within the next couple of days.