Why is my ph always rising in my aquariums?

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,
I keep bettas which prefer soft water, so I suppose I’ll go with the dilution route. As for the softened water… my biggest concern was actually the lack of minerals, but now I’m worried about the sodium too. The problem with the outside faucet is that the water freezes and won’t come out. If I bought bottled spring water, tested it beforehand to make sure it was of similar parameters to my aquarium water, and then add distilled water to get to the ideal ph of 7-7.5, would that work? Obviously I’d have to change the ph very slowly over time. If not, what might you suggest? Thanks for all the helpful replies btw!!
 
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First I would pin down the actual GH and KH so weknow what you are dealing with here. This is also important because when you dilute the tap water you want to know roughly what will result. It is proportional, so for example using 50% tap water and 50% "pure" water will dilute the GH/KH by half. The pH will work itself out accordingly.

"Pure" water refers to RO (reverse osmosis) water, distilled water, or rainwater.

For a single betta, in presumably a smaller tank (5 or 10 gallons, or similar) the effort would not be as much as it would for a much larger tank, so it is more manageable. But let's pin down the GH/KH.
 
hing is, my water is run through a water softener so not sure how that plays into this.
You water softener removes GH calcium and magnesium) by reacting it with sodium chloride. this removes all of the calcium and magnesium. It leaves behind sodium bicarbonate. Sodium bicarbonate will increase PH potentially above a PH of 8.

Now you are fertilizing your water with thrive. Like most fertilizer it doesn't include Calcium an essential plant nutrient. So it is very likely you aquarium is deficient in calcium so your plants maybe growing slower than normal and may not havenormal looking leaves. A Magnesium deficiency is also possible since most fertilizers on the market don't have enough magnesium. Thrive has Magnesium but I don't know how much.

The GH test detects calcium and magneisum.
The KH test detects carbonates.

PH is primarily covered by the levels Potassium, sodium,Calcium, Magnesium, sulfur, and to a lesser extent chlorine (also an essential plant nutrient but plant prefer it calcium chloride or potassium chloride with is safe for fish and shrimp). Most of the times calcium and magnesium are in the forms of a sulfate salt, or a chloride salt which have no effect on PH. Sometimes they are in the form of calcium carbonate or magensium carbonate. These will push the PH up to 7 but not higher. If PH if higher than 7 calcium and magnesium carbonate will become insoluble precipitate out of the water.

Sodium and potassium are normally pressent as a salt Potassium chloride or potassium sulfate and sodium is also commonly found as a sulfate or chloride. These again have no effect on PH. However if they are in the form of a carbonate they can push the ph up to a value exceeding 9. The final PH will depend on ratio of carbonates to acids (sulates and chlorides).

In your case the carbonates from your water softener are likely the cause of your high PH. mixing unsoftened water with RO water is probably your best solution. Buying RO water however is expensive Installling an under sink RO system does cost about $100 but in the long run it will be vastly cheaper than buying RO. After that I would put some crushed coral in your filter. It is mainly calcium with a small amount of magnesium. if sulfate and chloride levels get hgh and the ph starts dropping the crushed coral will start to dissolve and react with the sulfated chloride and push the PH back up to 7. This will push up the GH a small amount but that is not dangerous. You only will need about a spoon full of crushed coral to do this and when performing regular maintenance add more iff necessary.

Also note that sodium and potassium levels together affect the self to your fish and shrimp. Too much sodium is bad. Too much potassium is also bag. From everything I have see is too much potassium is probably more dangerous than too much sodium. In My RO water tank I prefer to keep sodium and potassium levels about equal. All of the elements I have listed are essential for plants and animals to be healthy. Animals get most from food but can absorb them from the water. Plants need them to be dissolved in the water.
 
First I would pin down the actual GH and KH so weknow what you are dealing with here. This is also important because when you dilute the tap water you want to know roughly what will result. It is proportional, so for example using 50% tap water and 50% "pure" water will dilute the GH/KH by half. The pH will work itself out accordingly.

"Pure" water refers to RO (reverse osmosis) water, distilled water, or rainwater.

For a single betta, in presumably a smaller tank (5 or 10 gallons, or similar) the effort would not be as much as it would for a much larger tank, so it is more manageable. But let's pin down the GH/KH.
Well, since I probably won’t be using my tap water since it’s run through a softener wouldn’t I have to just test the bottled spring water’s gh and kh and adjust accordingly how much I dilute it?

I went ahead and tested the gh and kh of the tap anyways,
Gh is around 20 dGH and kh is around 15 dKH

I was surprised gh is so high since I figured the softener would lower that?

Anyway, lemme know how to dilute bc I have to do a water change in a few days! I’m gonna look into it myself a bit as well

Also someone mentioned getting an RO system —I should probably say for context, I’m a teenager, and don’t really have control over what fixtures are in the house lol. I mentioned getting an RO system to my mom after the softener was installed (offered to pay for it too) but she’s not into the idea for whatever reason.
 
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You water softener removes GH calcium and magnesium) by reacting it with sodium chloride. this removes all of the calcium and magnesium. It leaves behind sodium bicarbonate. Sodium bicarbonate will increase PH potentially above a PH of 8.

Now you are fertilizing your water with thrive. Like most fertilizer it doesn't include Calcium an essential plant nutrient. So it is very likely you aquarium is deficient in calcium so your plants maybe growing slower than normal and may not havenormal looking leaves. A Magnesium deficiency is also possible since most fertilizers on the market don't have enough magnesium. Thrive has Magnesium but I don't know how much.

The GH test detects calcium and magneisum.
The KH test detects carbonates.

PH is primarily covered by the levels Potassium, sodium,Calcium, Magnesium, sulfur, and to a lesser extent chlorine (also an essential plant nutrient but plant prefer it calcium chloride or potassium chloride with is safe for fish and shrimp). Most of the times calcium and magnesium are in the forms of a sulfate salt, or a chloride salt which have no effect on PH. Sometimes they are in the form of calcium carbonate or magensium carbonate. These will push the PH up to 7 but not higher. If PH if higher than 7 calcium and magnesium carbonate will become insoluble precipitate out of the water.

Sodium and potassium are normally pressent as a salt Potassium chloride or potassium sulfate and sodium is also commonly found as a sulfate or chloride. These again have no effect on PH. However if they are in the form of a carbonate they can push the ph up to a value exceeding 9. The final PH will depend on ratio of carbonates to acids (sulates and chlorides).

In your case the carbonates from your water softener are likely the cause of your high PH. mixing unsoftened water with RO water is probably your best solution. Buying RO water however is expensive Installling an under sink RO system does cost about $100 but in the long run it will be vastly cheaper than buying RO. After that I would put some crushed coral in your filter. It is mainly calcium with a small amount of magnesium. if sulfate and chloride levels get hgh and the ph starts dropping the crushed coral will start to dissolve and react with the sulfated chloride and push the PH back up to 7. This will push up the GH a small amount but that is not dangerous. You only will need about a spoon full of crushed coral to do this and when performing regular maintenance add more iff necessary.

Also note that sodium and potassium levels together affect the self to your fish and shrimp. Too much sodium is bad. Too much potassium is also bag. From everything I have see is too much potassium is probably more dangerous than too much sodium. In My RO water tank I prefer to keep sodium and potassium levels about equal. All of the elements I have listed are essential for plants and animals to be healthy. Animals get most from food but can absorb them from the water. Plants need them to be dissolved in the water.
My plants are growing surprisingly well, but I have noticed that my anubias have slightly crinkled leaves which could point to a calcium deficiency like you mentioned. I had assumed it was because I have a lot of fast growing plants that sucked it up first.
 

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If the GHis actually as high as 20 dH, there is more than sufficient calcium.
 
Well, since I probably won’t be using my tap water since it’s run through a softener wouldn’t I have to just test the bottled spring water’s gh and kh and adjust accordingly how much I dilute it?

I went ahead and tested the gh and kh of the tap anyways,
Gh is around 20 dGH and kh is around 15 dKH
If that tap is softened water then your water softener is not working or it ran out of salt. I would expect the GH for softened water to be about 1 or less but I don't have a water softener. Check other facets around the house and outside. Typically softened water is plumbed to interior facets while exterior facets stay on the hard water line. You need to figure out what is going on.
My plants are growing surprisingly well, but I have noticed that my anubias have slightly crinkled leaves which could point to a calcium deficiency like you mentioned.
Your anubias is showing mostly magnesium deficiency. Wrinkled leaves are typical for Magnesium but for Calcium typically the type of the leaf is hooked down. It probably is just barely getting enough GH. This also indicates your water softener was once working. Also the plant in the background show evidence of a mobile nutrient deficiency.

Mobile nutrients are nutrients the the plant can strip from old leaves and move to support new growth . The older leaves then die and fall off. typically a leaving a bare stem with new growth at the end of the stem. Mobile nutrients are Nitrogen (N), potassium, (K) Magnesium (Mg), phosphate (P), chlorine (Cl), Molybdenum (Mo and nickel (Ni). .Again pointing to magnesium. molybdenum and nickel are also possible especially with softened water. But generally you only need 0.001ppm for Mo and Ni while Magnesium (Mg)
 
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You do not to buy the GH/KH kits. Take a day old water saample from your tap water to the store where you shop for fish etc. and ask them to test those things for you. Most stores will do this.

Most, of the things mechanical filtration removes from the water are organic. My tanks which use Hamburg Mattenfilters are the clearest ones i have. And they are used for breeding plecos which are notoriously messy fish. To get a really good grasp on how filtration works, have a read here: Aquarium Filtration

Filter community

The term filter for a Mattenfilter is actually misleading. The purpose of the foam is not to filter the water as is often assumed. The foam serves as the habitat for a vast array of microorganisms that include bacteria, archaea, worms, ciliates, flagellates, and many others. These microorganisms live in a community that is based on biofilms. The biofilms are created by bacteria that secrete extracellular polymeric substance (EPS), which is often called “slime”. The community forms a bioreactor that processes the waste and turns it into food and energy for its members, and ultimately into organic or inorganic products that are then used by plants, evaporate, or removed by water changes. It takes a considerable amount of time to establish this “filter community”; consequently, it is very important not to disturb it unless absolutely necessary. The brown filter sludge in a filter is for the most part alive and not simply waste. Removing this mud does more harm than good. The Mattenfilter with its large inflow area and specific surface is ideal to maintain the filter community long term since it works for years.

Mattenfilter working principle

The Mattenfilter works like the soil, sand, and gravel layers along creeks and river banks. This area is called the riparian zone from the Latin term ripa = river bank. Sediments are trapped, which creates clear water, and dissolved pollutants are processed by microorganisms, which improves water quality via biofiltration.
from http://www.swisstropicals.com/library/mattenfilter/

I also lower the hardness and pH in one tank using pure water. I make it myself and have and RO?DI unit for this. The DI part is a deionizing resin. It removes the things the RO membrane doesn't.
An ion is an atom or group of atoms in which the number of electron s is different from the number of protons. If the number of electrons is less than the number of protons, the particle is a positive ion, also called a cation. If the number of electrons is greater than the number of protons, the particle is a negative ion, also called an anion.
Ions you should easily recognize are ammonium, nitrite and nitrate.

Lowering the pH from its natural level requires removing minerals etc. from the water. THe ones that contribute ti KH are the most important here.

Buffering Capacity (KH, Alkalinity)​

Buffering capacity refers to water's ability to keep the pH stable as acids or bases are added. pH and buffering capacity are intertwined with one another; although one might think that adding equal volumes of an acid and neutral water would result in a pH halfway in between, this rarely happens in practice. If the water has sufficient buffering capacity, the buffering capacity can absorb and neutralize the added acid without significantly changing the pH. Conceptually, a buffer acts somewhat like a large sponge. As more acid is added, the ``sponge'' absorbs the acid without changing the pH much. The ``sponge's'' capacity is limited however; once the buffering capacity is used up, the pH changes more rapidly as acids are added.
Buffering has both positive and negative consequences. On the plus side, the nitrogen cycle produces nitric acid (nitrate). Without buffering, your tank's pH would drop over time (a bad thing). With sufficient buffering, the pH stays stable (a good thing). On the negative side, hard tap water often almost always has a large buffering capacity. If the pH of the water is too high for your fish, the buffering capacity makes it difficult to lower the pH to a more appropriate value. Naive attempts to change the pH of water usually fail because buffering effects are ignored.

In freshwater aquariums, most of water's buffering capacity is due to carbonates and bicarbonates.

We cannot change the pH in a tank without first changing the KH. Raising pH by adding KH is easy, removing it to lower pH is not. So instead of that we use RO or RO/DI water mixed with our tap to produce the end result we want. In some cases the tap water available is so awful it becomes easier to use 100% RO/DI (pure water) and then add back the needed minerals etc. the fish, bacteria and plants need.

Yes, plants will use ammonium faster than bacteria can use ammonia. However, no matter how many plants one has in a tank, there will still be some amount of nitrifying bacteria as well. The plants may be fast, but they are not fast enough to prevent there being some amount of both ammonia and ammonium in tanks. This changes basically to all ammonium as the pH hits 6.0 and below. Bear in mind one can have a tank where plants do most, but not all the nitrifying. There are always some number of bacteria. On the other hand, one can have a tank devoid of live plants with almost all the nitrification being done by bacteria. I say almost all because algae can also use ammonium.

Next, more modern sodium based water softener remove pretty much all of the salt for the water before it exits the unit into the house water supply. This has made salt less of a problem for folks with FW tanks. But it has made other problems for the environment. That very salty water has to be dumped somewhere and that is usually outside. High concentrations of salt are not real good for plants and things living in the solid where that briney water ends up.

There are softeners that use Potassium Chloride instead of salt but that costs a lot more than salt. There are other options that use electricity to do the job, but then your electric bill will go up. Finally, here are other options as well.
https://water.unl.edu/article/drinking-water-wells/salt-free-water-softener-alternatives
 
The unsoftened tap water is supposed to have a GH of 21 dH.





There's definitely something going on.
The unsoftened tap water is supposed to have a GH of 21 dH.





There's definitely something going on.
I retested the tap today and gh was 1-2 at most, and kh was 15. So, the softener is clearly back on. I tested the outside faucet as well, weather was pretty mild today, and it was 21 dGH and around 15 dKH.
 
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If that tap is softened water then your water softener is not working or it ran out of salt. I would expect GH for softened water to be about 1 or less but I don't have a water softener. Checker other facets around the house and outside. Typically softened water is plumbed to interior facets while exterior facets stay on the hard water line. You need to figure out what is going on.

Your anubias is showing mostly magnesium deficiency. Wrinkled leaves are typical for Magnesium but for Calcium typically the type of the leaf is hooked down. It probably is just barely getting enough GH. This also indicates your water softener was once working. Also the plant in the background show evidence of a mobile nutrient deficiency.

Mobile nutrients are nutrients the the plant can strip from old leaves and move to support new growth . The older leaves then die and fall off. typically a leaving a bare stem with new growth at the end of the stem. Mobile nutrients are Nitrogen (N), potassium, (K) Magnesium (Mg), phosphate (P), chlorine (Cl), Molybdenum (Mo and nickel (Ni). .Again pointing to magnesium. molybdenum and nickel are also possible especially with softened water. But generally you only need 0.001ppm for Mo and Ni while Magnesium (Mg)
Yep the softener is back on now, not sure exactly why it was off. I tested the tap again, gh was basically 0. Kh around 15 dKH.

Thanks for letting me know about the nutrients. Would just quitting using the softened water fix that problem, or should I get new fertilizer? My unsoftened water has looots of minerals. I assume the plant in the back you were talking about is the crypt, I’ve been so frustrated with it melting lately lol.
 
Thanks for letting me know about the nutrients. Would just quitting using the softened water fix that problem, or should I get new fertilizer? My unsoftened water has looots of minerals.

You can get a Gh booster like Seachem Equilibrium and dose it to achieve a GH of 2 which could be sufficient for plants. However the high KH causeless another issue.

The KH will react with the KH in the micro nutrients in your fertilizer (Manganese (Mn), Zinc (Zn), and Copper (Cu)) creating insoluble micro carbonates which the plants cannot use. Not the GH booster will want to push the PH down. but your high KH will override that. So I wouldn't expect the PH to change that much.

So you either need to dose fertilizer once a day or reduce the KH. You might be able to zoom up with a mix of hard water with softened water that might work ours bottled water or RO water. UnfortunelyIdon't know of a commercial fertilizer that will fix this issue without causing other issues. For my 100% RO water tank I am making my own fertilizer but that is not simple and you would have to buy the ingredients and scale and and with some math. But even then I still had to keep my pH slightly acidic and kH at zero to get good results.
 

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