Manually buffering destroys the natural buffering capacity of your water, which can lead to pH swings.
This is why PH was something that didn't bother me before. I knew 7.4 wasn't ideal but 8.2 is just ridiculously high to me. I will be buying that nitrate filter because I don't enjoy chasing my nitrate level but I think you're right. I kept an eye on the parameters after the gravel change and nothing went up except the PH
However, a change in pH from 7.4 to 8.2 would not wipe out a tank. Tanks have changes like that everyday.
The pH of lakes and streams often changes during the day in response to photosynthetic activity. In ponds having poorly buffered (low alkalinity) waters, the pH may fall to approximately 7 in the early morning and increase to 9 or more in the afternoon (Boyd 1990). Good fish production usually can be maintained in spite of these daily fluctuations. In most lakes and ponds, diurnal pH fluctuations during the summer, when photosynthetic activity peaks, are generally less than 2 pH units, while in streams are generally less (e.g., 0.5-1.0 units). Unless diurnal fluctuations result in ambient pH falling below 6 or being elevated above 9, they generally have no adverse impact on aquatic life.
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Based on findings from these studies and personal communications with CDFG fish pathologists (Modin, pers. comm., 1998), it is concluded that neither acute mortality nor chronic sub-lethal effects would be expected in fish experiencing rapid pH changes when all pH levels to which fish are exposed remain within the range of 6.5 to 8.5.
It didn't wipe out my tank only a few out of all of them died but then if that's the case what on earth would've caused this?
Hi
I've had an entire shoal of corydoras, a few neon tetra and my bristlenose pleco die on me in the past few weeks with no explanation and my cherry barbs have been looking rather listless.