Fluctuating pH

Banafish

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So based off the advice of a few members, I have done a test (results below in photos, go into the photos to see the info), and the source of my pH fluctuations (rising steadily) is probably not due to the substrate. I put about half an inch of the substrate in a bucket of water and left it for 6 days, the pH was actually lower than a cup of water that I left out for the same amount of time. What should I do now?

Thanks!
 

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It's a bit hard to read due to small images and I'm half blind but the pH appears to be going up in all containers including the control bucket. That's weird.

Any idea what the KH (carbonate hardness) and GH (general hardness) of the water is?

Maybe try aerating a bucket of water for a week and check the pH on that.
 
@Colin, this is carrying on from another thread, here:

There are some unknowns in this. First, the water is forest stream water. The GH and KH are 2 ppm (if memory serves me, but they are very low) and the pH is fluctuating in the stream water. This may be related to the environment, which can fluctuate seasonally.

Then there is the Flourite substrate. Seachem claim it does not alter pH; I had it several years back and frankly I cannot remember one way or the other. I only know it was next to useless as a substrate and after two years I tossed it in a hole in the back yard and buried it.

@Banafish is there any other substance in the tank? Like the Flourite, wood, rock...or added water substances/additives...anything at all.?
 
@Colin, this is carrying on from another thread, here:

There are some unknowns in this. First, the water is forest stream water. The GH and KH are 2 ppm (if memory serves me, but they are very low) and the pH is fluctuating in the stream water. This may be related to the environment, which can fluctuate seasonally.

Then there is the Flourite substrate. Seachem claim it does not alter pH; I had it several years back and frankly I cannot remember one way or the other. I only know it was next to useless as a substrate and after two years I tossed it in a hole in the back yard and buried it.

@Banafish is there any other substance in the tank? Like the Flourite, wood, rock...or added water substances/additives...anything at all.?
I have a piece of driftwood and some plants in the tank, that’s all. Could the filter media be affecting pH? I use filter floss top layer, and then seachem matrix. I only use Flourish Comprehensive Supplement.

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According to the Seachem site, Matrix does not affect pH. It is supposed to partially reduce nitrate, which I would question. But not pH. I just noticed you are dosing two doses of Flourish Comp, this may be too much, as I can see some algae on the glass (?). That substrate, is just Flourite?
 
OK. When you collect the rainwater from the stream, is it put through any type of filter or substance before you use it, or does it just go in the tank?
 
The water is collected in an external tank in the forest. As it is pumped up to the house it goes through a few different filters and comes out as tap water.

I just use my tap water for my fish tank.
 
The water is collected in an external tank in the forest. As it is pumped up to the house it goes through a few different filters and comes out as tap water.

I just use my tap water for my fish tank.

Sorry for so many questions, but something is doing something to the water for the pH to vary so much so often. Do these filters do anything, I mean chemically?
 
Sorry for so many questions, but something is doing something to the water for the pH to vary so much so often. Do these filters do anything, I mean chemically?
Hmm, I actually don’t know, I will have to check
 
If the pH of the stream water is fluctuating regularly, there is a major problem and someone could be adding stuff to the water (probably illegally).
Have you walked up the creek to its starting point?
Someone might be mining up that way and dumping the toxic waste water into the creek. If they are mining a few days a week, the pH could change when they are there and go back to normal when they aren't.

A word of caution, if you do go up the creek and find something, get out of there asap and call the police and water company.

I have surveyed waterways all over the south-west of WA and regularly throughout the year. There is very little variation in pH or GH during the year. There might be a slight increase in pH during winter when the rain dilutes the rivers, and the pH might drop a bit in summer as the water level reduces. But I have never seen the pH fluctuate rapidly or randomly.
 
Sorry for so many questions, but something is doing something to the water for the pH to vary so much so often. Do these filters do anything, I mean chemically?
Ok so I don’t think they do, we use UV sterilisation.
 
Ok so I don’t think they do, we use UV sterilisation.

OK, so I fall back to Colin's post above on possible physical issues with the stream. Beyond that, I don't know what cold be causing pH fluctuations.
 
If the pH of the stream water is fluctuating regularly, there is a major problem and someone could be adding stuff to the water (probably illegally).
Have you walked up the creek to its starting point?
Someone might be mining up that way and dumping the toxic waste water into the creek. If they are mining a few days a week, the pH could change when they are there and go back to normal when they aren't.

A word of caution, if you do go up the creek and find something, get out of there asap and call the police and water company.

I have surveyed waterways all over the south-west of WA and regularly throughout the year. There is very little variation in pH or GH during the year. There might be a slight increase in pH during winter when the rain dilutes the rivers, and the pH might drop a bit in summer as the water level reduces. But I have never seen the pH fluctuate rapidly or randomly.
Could it be that the water just takes a long time to outgas the CO2? Because today I tested the control water and it is still at 7.2

However the tank is at 7.8 after I did a WC yesterday.
 
Could it be that the water just takes a long time to outgas the CO2? Because today I tested the control water and it is still at 7.2

However the tank is at 7.8 after I did a WC yesterday.
Carbon Dioxide (CO2) and other gasses (nitrogen and oxygen) should stabilise in water within about 24 hours, sooner if the water is aerated. The fact the pH continues to change after a few days to a week would suggest something weird is going on.

You could buy a CO2 and O2 test kit from a pet shop and test the water. The shop will probably have to order the kits in for you but they are available and you could check the levels to see if they are affecting the water.
 

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