Biological filters and pH

[NancyMc]

Do you think that pH affects the efficiency of biological filters? For instance, if the pH is significantly low (e.g. 6) that the biological filter will not work as well? I know that pH is supposed to be between 7.5 and 8.5 but if the pH falls below that, will the filters be affected?

 

[Mmathis]

It’s more important for the pH to be stable than it is for it to be at any particular number. IOW, you don’t want big swings from day to day……but to consistently stay in a range. As far as the efficiency of the biological filter, I don’t know what numbers the bacteria prefer, but again, stability and consistency will be better than big spikes. Hope that helps.

 

[GBBUDD]

Ph is most definitely affected by high or low pH low pH is acidic and kills bacteria. So the closer to neutral the better. But being on the high side is far better than low. 7 to 8.5 it thrives.

 

[WaterGardener]

I agree. Bacteria can't survive well, much less thrive, in acidic water. Few things can. Most fish don't do well swimming in acidic water either. That is a pretty hostile environment for them and for bacteria to live in.

Beneficial bacteria needs three things: the proper temperature, oxygenated water, and the right pH. A pH of 6 makes things very difficult for them.

 

[NancyMc]

This has certainly been a lesson experience about controlling the pH and the KH. I have too many fish for the size of my overwintering pond. I have three biological filters running and two aerators. However, the pH really wants to be acidic, as expected. I started adding baking soda to raise the pH. I was aiming for 8.4 but found I had added a lot of baking soda and the pH wouldn’t go above 8-8.2. I finally tested the KH and it was significantly higher than 200! It is so much less trouble to test just pH and not follow up with KH but lesson learned! I noticed that since I raised the pH though what was slightly cloudy water is now crystal clear…and yes, I will be cleaning the filters, which is even more of a pain than testing KH but it needs to be done.

 

[WaterGardener]

That KH is fine. It can be high without any negative effects, so don't worry about that. It just provides more buffer for the pH.

Your water is fine if the pH doesn't go over 8.2. it would be lacking in calcium if it went over 8.3. Is there a reason you wanted it to be higher? It's actually a good thing that it didn't continue to climb.

One thing you do need to be cautious about is raising the pH too quickly. It should be done slowly over days, even a week or more, not over hours. A sudden change can be too stressful for the fish, so go slowly with those changes.

 

[NancyMc]

I was aiming for a higher pH because it seemed from previous discussions that 8.4 would be more suitable. I do always do my pH adjustments over several days thanks to previous recommendations. Patience is a virtue, one I don’t have a lot of, but I am doing as I was told!!. I can’t thank you enough for all of your help. What a great group!

 

[GBBUDD]

I was aiming for a higher pH because it seemed from previous discussions that 8.4 would be more suitable. I do always do my pH adjustments over several days thanks to previous recommendations. Patience is a virtue, one I don’t have a lot of, but I am doing as I was told!!. I can’t thank you enough for all of your help. What a great group!

I'm not sure what test kit you are using but I have yet to find one i can tell clearly if I'm 8 or 8.2 or 8.4.

Something as simple as leaving the test bottle in the sun could I'm not saying it will but could change the results of the test. I do know it's recommended to keep them in above 40 I believe and under 100.
Once you get to know your pond I think you'll find if you keep an eye on the kh and it's around 150 to 200 your pH you'll find will be stable. So the kh could be the only test needed once you know your pond

 

[Mmathis]

 

[NancyMc]

View attachment 166656

Wow Wow Wow! How did you find this?

 

[GBBUDD]

Wow Wow Wow! How did you find this?

Alkalinity is what kh is all about. I'm very surprised there is no mention of kh helps keep the ph stable and thus keeps it from crashing . Quick pH swings can kill fish which often is caused by acid rain

 

[Mmathis]

Wow Wow Wow! How did you find this?

Google. I typed in “ideal pH for nitrifying bacteria in a pond.”

 

[Lisak1]

I think that answers the question - nature finds a way. If one bacteria loves it at 6.5 another one is gonna wanna live at 9.0.

 

[GBBUDD]

They have found life and bacteria in places previously thought impossible. Such as the boiling hot pools in yellowstone, in extremely costic and acidic waters, the blues red greens yellow are all different types of bacteria or microbes. The volcanic vents at the bottom of the ocean that are silicone based life, where we though all life had to be carbon based.

LIFE FINDS A WAY

 

[Lisak1]

I've seen the same with the algae in our pond. During the hot months we have one type of algae that grows. When it's frigid that algae disappears and we get a whole other kind of algae growth going on. And yes, it's still growing when the pond is freezing cold. Nature runs the gamut - not much you can throw at her that she can't adapt to.