Why is my ph always rising in my aquariums?

You first need to pin doen the pH of the tap water. I suspect this is likely the issue here. As someone mentioned, let a glass of fresh run tap watersit 24hours, then test the pH. The issue here is that dissolved CO2 in the tap water can oftenbe high, lowering the pH. But when the CO2 out-gasses, the actual pH is restored, and that is what you have to work with.

As for lowering, the only way to safely and effectively do this is by diluting the tap water with pure water. I won't get into this as it may not be necessary. But you do need to find out the GH and KH of your tap water. This may be posted on the water authority's website. These three parameters are closely connected and the GH and KH affects the pH to varying degrees so all three values must be determined.
 
You first need to pin doen the pH of the tap water. I suspect this is likely the issue here. As someone mentioned, let a glass of fresh run tap watersit 24hours, then test the pH. The issue here is that dissolved CO2 in the tap water can oftenbe high, lowering the pH. But when the CO2 out-gasses, the actual pH is restored, and that is what you have to work with.

As for lowering, the only way to safely and effectively do this is by diluting the tap water with pure water. I won't get into this as it may not be necessary. But you do need to find out the GH and KH of your tap water. This may be posted on the water authority's website. These three parameters are closely connected and the GH and KH affects the pH to varying degrees so all three values must be determined.
okay. I’ll reply again once I can retest the tap and figure out my GH and KH, and hopefully that will help with finding a solution. At least the ph isn’t so high that it’s hurting my fish and inverts, my shrimp especially are doing pretty great, breeding a lot and molting
 
I reexamined your photos and see you have a double sponge filter in the betta tank. I can't tell what the other tank has. In any case, that is good. Here is what I do and it works: Clean one sponge the first week and the other the second week. I took sharp scissors and cut a very small piece out of one of the sponges. It looks like small 'V' and makes it easy to remember which one to clean. All of my 'V' sponges get cleaned the first and third week and those without the cut get cleaned on the second and fourth week. I like that you are not racing around to solve the issue. Besides, perhaps your fish and inverts will be fine as is? Hope this helps!
 

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I reexamined your photos and see you have a double sponge filter in the betta tank. I can't tell what the other tank has. In any case, that is good. Here is what I do and it works: Clean one sponge the first week and the other the second week. I took sharp scissors and cut a very small piece out of one of the sponges. It looks like small 'V' and makes it easy to remember which one to clean. All of my 'V' sponges get cleaned the first and third week and those without the cut get cleaned on the second and fourth week. I like that you are not racing around to solve the issue. Besides, perhaps your fish and inverts will be fine as is? Hope this helps!
It does! Although this does make me curious, what about the people with botanical tanks who completely don’t touch their substrate, allowing detritus to build up? sorry to go on and on, but I like talking about this stuff. Why don’t they encounter similar issues? And yeah, if there’s anything I’ve learned while keeping fish is nothing good happens quickly, including finding solutions to issues. If they’ve survived this long they can wait a few more weeks/months for me to figure it out.
 
What similar issues are you referring to?
 
What similar issues are you referring to?
Any issues relating to excess decaying matter, like why is it important to remove that stuff from a filter if some people encourage leaving it on the substrate? As long as the filters still running and isn’t being blocked, I don’t see the difference. Sorry for being unclear 😅
 
Any issues relating to excess decaying matter, like why is it important to remove that stuff from a filter if some people encourage leaving it on the substrate? As long as the filters still running and isn’t being blocked, I don’t see the difference. Sorry for being unclear 😅

There are two very different factors here, the substrate and the filter are very different "operators" in an aquarium.

The filter serves one or two purposes. The first, common to all filters, is the mechanical removal of particulate matter from the water to keep it clear. A second purpose is biological filtration, involving nitrifying bacteria that assimilate the ammonia, producing nitrite which other nitrifying bacteria use producing nitrate. In planted tanks this biological filtration is totally unnecessary, and should never be "encouraged," because it is competing with the plants for the ammonia. Plants actually take up ammonia much faster than the nitrifying bacteria, so the plants "win" the race, but this only illustrates why biological filtration is less than necessary. It will still occur regardless, but at a minimal level. Always assuming the plants are healthy and capable of dealing with things.

Obviously the filter media must be kept clean of all that "gunk," or it will not be able to do a good job of the mechanical filtration. And all those organics sitting in the filter only risk nitrates, though again in balanced planted tanks this is or should be less of an issue because the plants are hopefully out-competing the nitrifying bacteria. Still, it cannot hurt to rinse the filter media at every weekly water change. I always have in 20 or more years at least for internal filters like sponge; canisters are a bit different.

Now, the substrate is a very different issue. This is the foundation of an aquarium. The many species of bacteria that live in a healthy substrate far surpass those in the filter with respect to filtration other than nitrifying. The substrate should not clog up with detritus...that is a sign of too many fish, or too large fish, or too much food being fed. My Corydoras tank ran for years and I never touched the sand, and when I disturbed it to plant or something, there was remarkably little mess stirred up. The cories poking into it continually, plus rooted plants, plus Malaysian Livebearing Snails, all worked to keep the substrate "sweet and fresh" as one book put it [can't remember the book, it was some years back now]. What goes on in the substrate, again assuming the tank is balanced biologically, is crucial to having a healthy aquarium. You can shut off the filter, but you cannot do without a suitable substrate.

Now, I did have some tanks in which I had to clean into the substrate at each water change, the open areas anyway (never move wood or rock to clean under it, this is a serious risk). Each aquarium can be quite different; the same natural laws of biology and chemistry will apply, but they may play out differently.
 
There are two very different factors here, the substrate and the filter are very different "operators" in an aquarium.

The filter serves one or two purposes. The first, common to all filters, is the mechanical removal of particulate matter from the water to keep it clear. A second purpose is biological filtration, involving nitrifying bacteria that assimilate the ammonia, producing nitrite which other nitrifying bacteria use producing nitrate. In planted tanks this biological filtration is totally unnecessary, and should never be "encouraged," because it is competing with the plants for the ammonia. Plants actually take up ammonia much faster than the nitrifying bacteria, so the plants "win" the race, but this only illustrates why biological filtration is less than necessary. It will still occur regardless, but at a minimal level. Always assuming the plants are healthy and capable of dealing with things.

Obviously the filter media must be kept clean of all that "gunk," or it will not be able to do a good job of the mechanical filtration. And all those organics sitting in the filter only risk nitrates, though again in balanced planted tanks this is or should be less of an issue because the plants are hopefully out-competing the nitrifying bacteria. Still, it cannot hurt to rinse the filter media at every weekly water change. I always have in 20 or more years at least for internal filters like sponge; canisters are a bit different.

Now, the substrate is a very different issue. This is the foundation of an aquarium. The many species of bacteria that live in a healthy substrate far surpass those in the filter with respect to filtration other than nitrifying. The substrate should not clog up with detritus...that is a sign of too many fish, or too large fish, or too much food being fed. My Corydoras tank ran for years and I never touched the sand, and when I disturbed it to plant or something, there was remarkably little mess stirred up. The cories poking into it continually, plus rooted plants, plus Malaysian Livebearing Snails, all worked to keep the substrate "sweet and fresh" as one book put it [can't remember the book, it was some years back now]. What goes on in the substrate, again assuming the tank is balanced biologically, is crucial to having a healthy aquarium. You can shut off the filter, but you cannot do without a suitable substrate.

Now, I did have some tanks in which I had to clean into the substrate at each water change, the open areas anyway (never move wood or rock to clean under it, this is a serious risk). Each aquarium can be quite different; the same natural laws of biology and chemistry will apply, but they may play out differently.
Thanks for such an in depth reply, I loved it! my sponge filters don’t accomplish much mechanical filtration, I’d say that my filters are primarily for water movement. Despite the lack of mechanical filtration, my water is very clear because I don’t disturb the substrate layer often. There’s visible mulm on the bottom of my shrimp tank, it ends up there rather than in my filter. It’s still not a lot. I can’t suck it up without taking baby shrimp with me lol. The nitrate it might be producing is no issue for me because like you said, the plants suck it right up. Plus, I’ve heard it can be beneficial to leave it, both for plants and for supporting a rich micro biome.

Whats so bad about letting the substrate be covered in detritus? I’ve seen some people do that on purpose. I don’t mean just adding a bunch of fish and having the bottom covered in waste in a week. Obviously that would be terrible, but letting it build up slowly over a long period of time in an understocked tank like it would in nature + adding botanicals and such. That way there’s time for microorganisms and bacteria to keep up with the biological load.

also, you mentioned it’s a bad idea to move large hard scape, why is that? I haven’t really heard that before

Anyway, I guess my point is since my sponge filters don’t accomplish lots of mechanical filtration and don’t get clogged often, there’s not as much reason to clean them every week as far as I can see. I’ll bump it up every two weeks just as a preventative measure, to make sure it’s not clogging.
 

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The talk about substrate brings into focus why I like under gravel filtration. We are all trying to duplicate nature which we will never do. In a river water always flows through the riverbed. With under gravel filtration the water always flows through the substrate. Seems to me to be the closest river situation.

That said, why not have a lot of stuff on the substrate.
1) In my case, with under gravel filtration, it would hamper the water flow.
2) When the stuff rots it could easily spike ammonia levels.
3) It can cause cloudiness in the water.
4) It can generate other toxins that can harm fish.

Don't get me wrong as there situations where you actually do want junk in/on the substrate but that is for specific fish. I'm not saying that you want zero garbage in the substrate especially in a heavily planted tank such as mine. Still, every time I do a water change, I still vacuum the substrate but stay away from plant roots. That is why I have two siphons with one being much smaller than the other. The bigger is to remove water. The smaller is to clean the substrate as it can get between plants.

Oh, as to your sponges they can actually look pretty clean yet still be clogged by slime and stuff that you just don't see.
 
The talk about substrate brings into focus why I like under gravel filtration. We are all trying to duplicate nature which we will never do. In a river water always flows through the riverbed. With under gravel filtration the water always flows through the substrate. Seems to me to be the closest river situation.

That said, why not have a lot of stuff on the substrate.
1) In my case, with under gravel filtration, it would hamper the water flow.
2) When the stuff rots it could easily spike ammonia levels.
3) It can cause cloudiness in the water.
4) It can generate other toxins that can harm fish.

Don't get me wrong as there situations where you actually do want junk in/on the substrate but that is for specific fish. I'm not saying that you want zero garbage in the substrate especially in a heavily planted tank such as mine. Still, every time I do a water change, I still vacuum the substrate but stay away from plant roots. That is why I have two siphons with one being much smaller than the other. The bigger is to remove water. The smaller is to clean the substrate as it can get between plants.

Oh, as to your sponges they can actually look pretty clean yet still be clogged by slime and stuff that you just don't see.
I pretty much do the same with my maintenance, besides the shrimp tank I do vacuum up the detritus, just not all of it. I’ve never done a full on mulm substrate I just think it’s an interesting idea to bring up

it does make sense that the sponges would get clogged by the smaller debris, good point 😅
 
You first need to pin doen the pH of the tap water. I suspect this is likely the issue here. As someone mentioned, let a glass of fresh run tap watersit 24hours, then test the pH. The issue here is that dissolved CO2 in the tap water can oftenbe high, lowering the pH. But when the CO2 out-gasses, the actual pH is restored, and that is what you have to work with.

As for lowering, the only way to safely and effectively do this is by diluting the tap water with pure water. I won't get into this as it may not be necessary. But you do need to find out the GH and KH of your tap water. This may be posted on the water authority's website. These three parameters are closely connected and the GH and KH affects the pH to varying degrees so all three values must be determined.
Okay… so, I tested the tap water after letting it sit out and yeah, the pH is 8.2 🥲 I still haven’t found the gh and kh, ordered some test strips that’ll be here in a few days.
 
Okay… so, I tested the tap water after letting it sit out and yeah, the pH is 8.2 🥲 I still haven’t found the gh and kh, ordered some test strips that’ll be here in a few days.

This confirms that the actual pH of the tap water is 8.2, and it will remain at or close to this in the aquarium--maybe. It all depends upon the GH and KH. Can't you find this from your water authority's website? No need for a test when you are likely to use it just once.
 
This confirms that the actual pH of the tap water is 8.2, and it will remain at or close to this in the aquarium--maybe. It all depends upon the GH and KH. Can't you find this from your water authority's website? No need for a test when you are likely to use it just once.
I’m not sure exactly how to find the gh and kh… I do know the water in my area is considered very hard, 22gpg

Thing is, my water is run through a water softener so not sure how that plays into this. Usually I use water from the hose for my aquariums since that’s the only faucet not run through the softener, but it’s too cold to do that right now.
 
Gpg is grains per gallon. This is almost the same as dH; 22 gpg = 21.1 dH and 380 ppm.

If you use water that's not been though the softener, you are using very hard water for the aquarium. But swapping to water which has been through the softener because of the temperature means you are now lowering the hardness in the tank with every water change which is not good for the fish in there.
If the water softener is the salt type, that's another problem as well as this type swaps the hardness minerals for sodium, and sodium in the water is not good for fish.

My 5.5 gal shrimp tank is stocked with shrimp, probably about 40 I’m not sure. My ten gallon has a betta, two nerites, and seven cherry shrimp.
With tanks this size, the easiest thing to do is use water that has not been through the softener and boil some of it to mix with the cold water to get the temperature right.
 
Your initial question concerned the rising pH, and we have now got the answer to that...the pH of the tap water is 8.2 so as I said, this will be the pH in the aquarium. The GH and KH are likely high (the GH certainly is), so these work with the pH to "buffer" it sand prevent fluctuations. The only way to lower the pH is to dilute the tap water with "pure" water. This reduces the GH and KH which in turn allows the pH to lower. This would mean preparing water outside the aquarium before adding it during water changes.

A for fish, species that require harder water will be fine. Soft water species will struggle, depending upon the species.

I concur with @Essjay on the softener. Find out how it works. If sodium is involved, this will not work for soft water fish as the sodium affects them,
 

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