Causes For High Ph?

Hey guys! I did some googling and couldn’t find much info, but I was wondering what the cause for a high pH is?

I went and got my tank water tested at Petsmart yesterday (this was my first time testing my water because I couldn’t afford an API Master kit until today, I was in between jobs), and the fish lady told me my pH was crazy high (she used less accurate test strips). She didn’t give me a number, but that scared me. So I bought TopFins pH decrease and used one dose of that yesterday. I got my Master kit today and tested my pH and it was 8.2. I used another dose and got it down to 8.0. My goal is 7.0, but I’m wondering why my pH is so high in the first place, and ways to stabilize and maintain it? The lady at Petsmart and I thought my tap water might be the cause of my high pH, but I tested the tap water by itself today and it was only 7.4. Will I have to use the pH decrease for maintenance always? Or are there other ways to lower the pH permanently so it’s stable? Thanks for any insight!

Tank specs: 10gal, 5 black neon tetras, 1 male betta, 2 mystery snails, live planted with a filter and bubbler. Just recently finished cycling.
pH-8.0
Ammonia-0
Nitrites-O
Nitrates-5.0ppm

 

Why are you shooting for a pH of 7? The fish you have have probably already acclimated to your pH. Lowering it with chemicals will only stress them. When you attempt to change your pH like that, it’ll end up bouncing back, stressing them again.

As to why your pH is high, that involves water chemistry, which isn’t all that simple. I don’t completely understand it all myself. Luckily for freshwater fish keepers, we don’t need to. What we shoot for is a stable pH. Generally, as long as your pH is stable and your fish are properly acclimated to your water, they will be happy and healthy (with the exception of a few species.)

Case in point: I have 16 rummynose tetras in my 75 gallon. They prefer acidic water according to just about every resource I’ve found. My pH is 7.8, and they’re thriving.

Test your pH at least once a week. As long as you’re keeping up with your water changes, it should be the same every time. That’s what’s important. And always take the advice you get from any pet store with a grain of salt!

 

Why are you shooting for a pH of 7? The fish you have have probably already acclimated to your pH. Lowering it with chemicals will only stress them. When you attempt to change your pH like that, it’ll end up bouncing back, stressing them again.

As to why your pH is high, that involves water chemistry, which isn’t all that simple. I don’t completely understand it all myself. Luckily for freshwater fish keepers, we don’t need to. What we shoot for is a stable pH. Generally, as long as your pH is stable and your fish are properly acclimated to your water, they will be happy and healthy (with the exception of a few species.)

Case in point: I have 16 rummynose tetras in my 75 gallon. They prefer acidic water according to just about every resource I’ve found. My pH is 7.8, and they’re thriving.

Test your pH at least once a week. As long as you’re keeping up with your water changes, it should be the same every time. That’s what’s important. And always take the advice you get from any pet store with a grain of salt!

Awesome, that makes sense! I looked up the “ideal” pH for the various species in my tank, but I couldn’t tell if the ideal number or stability was more important from what I was reading. I do know that you want it steady because fluctuations will shock your fish. So I think I’ll do my water changes and keep testing the pH now that I have my test kit, and make sure it stays steady. If my pH goes above 8.0 is that dangerous, or do you think my fish will acclimate to a certain point and I should just leave the water alone? Thanks!

 

HI Hannah,

What type of substrate do you have in the tank? I know certain types of substrate do raise the hardness and the ph of the water, such as crushed coral. Sea shells can also raise the ph as they slowly dissolve and release carbonates. Cuttle bone (that birds eat) will also do the same. I'm in the process of setting up a new guppy tank and they like a slightly higher ph so I'm using a crushed coral substrate and sea shells for this exact reason as my water in naturally softer and has a lower ph.

If you don't have any of those in your tank, then I'm at a loss!!

Certain types of wood will lower ph over time as they release tannins. I use quite a lot of wood in my main tank that has about 60 black neon tetras in as they like a slightly lower ph and my water is always around 6.4 (my tap water is 7 ph)

I don't like using the shop bought chemicals though that alter ph and I agree with others, a stable ph is more important than a correct number ph.

Its sometimes easier to plan and set up the tank for a certain ph range when setting it up rather than trying to change ph further down the line.

 

HI Hannah,

What type of substrate do you have in the tank? I know certain types of substrate do raise the hardness and the ph of the water, such as crushed coral. Sea shells can also raise the ph as they slowly dissolve and release carbonates. Cuttle bone (that birds eat) will also do the same. I'm in the process of setting up a new guppy tank and they like a slightly higher ph so I'm using a crushed coral substrate and sea shells for this exact reason as my water in naturally softer and has a lower ph.

If you don't have any of those in your tank, then I'm at a loss!!

Certain types of wood will lower ph over time as they release tannins. I use quite a lot of wood in my main tank that has about 60 black neon tetras in as they like a slightly lower ph and my water is always around 6.4 (my tap water is 7 ph)

I don't like using the shop bought chemicals though that alter ph and I agree with others, a stable ph is more important than a correct number ph.

Its sometimes easier to plan and set up the tank for a certain ph range when setting it up rather than trying to change ph further down the line.

I have normal gravel substrate with some decorative glass rocks, and a plastic hiding spot and ceramic one. Then I’ve got 5 live aquatic plants. I don’t think any of those raise pH, so I’ve no idea either why it’s high! I think I’ll ditch the chemicals for now (unless it somehow gets around 9.0, then I’ll worry). I’m gonna try driftwood or Indian almond leaves. Thanks for the advice!!

 

Rainbows live in brackish and depending on the species either hard or soft water in their natural environment. The 60 gallon tank I house mine in has a ph of 8.0-8.2 regularly. They spawn and show breeding behavior daily.

I 100% agree (and so do many respected hobbyists/writers) that stable ph is more important than maintaining a target for fish bred in captivity.

I would either return that bottle of ph decrease or pitch it!

Welcome to Fishlore Fellow Ohioan! I hope this advice wasn't from RMS Aquaculture or Something Fishy.

 

Rainbows live in brackish and depending on the species either hard or soft water in their natural environment. The 60 gallon tank I house mine in has a ph of 8.0-8.2 regularly. They spawn and show breeding behavior daily.

I 100% agree (and so do many respected hobbyists/writers) that stable ph is more important than maintaining a target for fish bred in captivity.

I would either return that bottle of ph decrease or pitch it!

Welcome to Fishlore Fellow Ohioan! I hope this advice wasn't from RMS Aquaculture or Something Fishy.

Okay cool, yeah I’m totally gonna ditch the pH decrease then. I just ordered some almond leaves so let’s hope they like it! Thanks for everyone’s help

 

Welcome to Fishlore!

Your pH is probably the number it is because of limestone. I live in Indiana and the water here gets filtered through limestone rock and that increases the pH. My pH is 8.2 here where I live.

 

I have normal gravel substrate with some decorative glass rocks, and a plastic hiding spot and ceramic one. Then I’ve got 5 live aquatic plants. I don’t think any of those raise pH, so I’ve no idea either why it’s high! I think I’ll ditch the chemicals for now (unless it somehow gets around 9.0, then I’ll worry). I’m gonna try driftwood or Indian almond leaves. Thanks for the advice!!

Yeah it doesn't sound like you have anything in there that would be causing the ph to increase naturally. I assume the plastic hiding spot you mentioned is a proper aquarium safe type of plastic? I know some plastics can leech chemicals into the water over time which could cause ph increase.

Diftwood and almond leaves would be a good idea. I would also consider adding some peat moss which can also lower ph. You can put some in a filter bag or something, or maybe add some to your filter (depending what kind of filter you have).

The wood and peat would also act as a natural filter to clean the water of contaminants which is an added bonus.

One other thing we haven't mentioned is how often do you change the water, and how much?

If your tap water is 7.4 ph and your aquarium water is 8.2 ph than simply doing more regular water changes will get the water closer to your tap water ph. 25% twice per week would be a good goal if you can spare that time and stick to it.

The water changes, coupled with some wood/leaves/peat might do the trick without the need of any artificial chemicals.

 

HI Hanna. Welcome to Fishlore! I'm not needed here because you're already getting good advice. However, from someone who also has rock-hard water and a high pH, I just want to reiterate that most species are not very sensitive to a pH outside of their recommended range... but all species, even the hardiest, are sensitive to sudden pH swings, which is just what products like pH Down do. I know you've said you'll ditch the pH altering product but just thought it might ease your mind about pH to hear the same advice from another aquarist.

 

I didn't realize you had live plants.

My water (I also live in Ohio, Cleveland area) has a ph of 8.2 because I have a high kh and gh (without getting too deep, I have hard water with good buffering capacity).
Your plants will make much better use of the hard water. I wouldn't try to adjust it personally.

 

Yeah it doesn't sound like you have anything in there that would be causing the ph to increase naturally. I assume the plastic hiding spot you mentioned is a proper aquarium safe type of plastic? I know some plastics can leech chemicals into the water over time which could cause ph increase.

Diftwood and almond leaves would be a good idea. I would also consider adding some peat moss which can also lower ph. You can put some in a filter bag or something, or maybe add some to your filter (depending what kind of filter you have).

The wood and peat would also act as a natural filter to clean the water of contaminants which is an added bonus.

One other thing we haven't mentioned is how often do you change the water, and how much?

If your tap water is 7.4 ph and your aquarium water is 8.2 ph than simply doing more regular water changes will get the water closer to your tap water ph. 25% twice per week would be a good goal if you can spare that time and stick to it.

The water changes, coupled with some wood/leaves/peat might do the trick without the need of any artificial chemicals.

Yes, the plastic hiding spot was made for fish and sold at petsmart so it should be safe! And my tank had just finished cycling so I’m still trying to figure out how often to water change. I think I’ll do 25% weekly like you suggested for now and see how that affects the pH! And I just ordered almond leaves, I think those two things combined should help my little guys be more comfortable in their water thanks for your help!

HI Hanna. Welcome to Fishlore! I'm not needed here because you're already getting good advice. However, from someone who also has rock-hard water and a high pH, I just want to reiterate that most species are not very sensitive to a pH outside of their recommended range... but all species, even the hardiest, are sensitive to sudden pH swings, which is just what products like pH Down do. I know you've said you'll ditch the pH altering product but just thought it might ease your mind about pH to hear the same advice from another aquarist.

That does reassure me, thanks! I think I’ll be turning to fish lore instead of petsmart for advice from now on

I didn't realize you had live plants.

My water (I also live in Ohio, Cleveland area) has a ph of 8.2 because I have a high kh and gh (without getting too deep, I have hard water with good buffering capacity).
Your plants will make much better use of the hard water. I wouldn't try to adjust it personally.

Okay, thanks! I think I’m gonna add some almond leaves and get the pH down just a tad (and also for the antibacterial properties), but since it seems my fish are acclimated and with the reassurance on this thread I’m not too worried.