I'm confused... My PH is always around 7.5 but my KH is at 89.5...Won't adding baking soda bring my PH up?You don't want to adjust the pH quickly. That will stress the fish. But if the KH is kept at a good level, the pH will not move. That's the whole point of KH. It keeps the pH stable. If you have very low or no KH, the pH can crash, killing the beneficial bacterial and your fish.
My pH is always 8.3 and has been for the last 8 years. It doesn't move because I keep a lot of KH in the system. KH is lowered by rain and by the acid produced as a by product of the nitrogen cycle. If it is allowed to be depleted, the pH will drop to acidic levels, very, very quickly.
Thank you for your quick response WaterGardener..I will add baking soda…my pond is only about 900 gallons…how much would you add at first? Do you think if I bring it up to 100 that would be okay? My plants are pale apparently due to low nitrate (my pond is only 5 months old ) so I hope a higher pH will not cause them to get worse…Yes, but it won't go above 8.3 or so, no matter how much baking soda you use. I keep the KH in my pond at 200 or more so my pH is at that level.
To me, your KH is a bit low. I like to see it around 100 at least. I have a bead type filter that I was told works best at a higher KH, around 200, so that is what I aim for.
A pH in the 8+ range is not too high. It's not a problem.
Thank you for taking the time to explain this to me. I will add the BS over a couple of daysThe plants will be fine. Mine grow like weeds.
I just looked up how much baking soda is needed to raise the KH 1 drop. I get 3.37 ounces, just under half a cup.
It won't hurt to use a full cup of baking soda or more. Having KH higher than 100 is a good thing in my opinion, and it's difficult to have too high a reading. I will boost mine to 300 or so before heavy rain to make sure I would have enough to buffer that extra acid from the rain. Some people keep theirs as high as 400., So there is a very large range.
If you want to be cautious with raising the pH, add that one cup measurement over 2 or 3 days and not all at once.