Why is my pH dropping??? Help!

This tank is driving me nuts! The pH keeps dropping, no matter what I do. I let the tap water sit 48-72 hours (with the conditioner added) before I do a water change. I test the water right before adding to the tank and the pH is always dead on 7.0. Within a day or two, it drops down in the 6 range eventually to 6.0. Even if I add pH Up it will drop back down. I've tried small, frequent changes (10-20%, every 2-3 days); I've tried huge weekly changes (50%). My fish are now hanging out at the top of the tank.

All other parameters in the tank are in a normal, safe range. I'm not over-feeding. There is no wood, live plants, or anything else that I think would lower pH. I do have a couple very small pieces of green slate, but as far as I know slate does not affect the pH.

What could be causing this? How can I fix it?

Any help greatly appreciated!!

 

What kind of Substrate are you using?

 

You most likely have soft water, which means your buffering capacity is low. Your waters hardness directly affects your stable pH level in your tank... pH altering products will NOT work and are not recommended.

Heres a sticky thread I wrote on changing your pH the correct way that might help, if you have any questions feel free to ask =)

https://www.fishlore.com/aquariumfishforum/threads/changing-your-ph.28528/

 

What kind of Substrate are you using?

I am using gravel.

You most likely have soft water, which means your buffering capacity is low. Your waters hardness directly affects your stable pH level in your tank... pH altering products will NOT work and are not recommended.

Heres a sticky thread I wrote on changing your pH the correct way that might help, if you have any questions feel free to ask =)

https://www.fishlore.com/aquariumfishforum/threads/changing-your-ph.28528/

Thanks for sharing that article!
We actually have moderate (maybe moderate-hard) water. It does become hard every 60-ish days when they flush the system. It's never been soft as far as I know...I test it at each water change.

 

I am using gravel.



Thanks for sharing that article!
We actually have moderate (maybe moderate-hard) water. It does become hard every 60-ish days when they flush the system. It's never been soft as far as I know...I test it at each water change.

Are you testing the hardness or just the pH... as just testing the pH will not give you a correct measurement of the actual buffering capacity

Also along with the question above... improper filter maintenance (ie not cleaning the gunk out regularly) and not doing thorough gravel cleaning can cause your pH levels to be low. The wastes (gunk) that build up release acids as they break down and lower the pH levels, part of the natural waste process. You however need to know your hardness(KH and GH) in an actual measurement for both your tank and your tap water to get to the root of your problem as this determines your pH directly.

Merged back to back posts.
Ken

 

GH is 7 and KH is 6 (holds true for my tap and tank water).
My charcoal filter is well maintained, I rinse it in tank water with every other water change. I rinse the bio filter in freshly-removed tank water when it gets noticably gunky (I've only had to rinse it one time which was after I returned from a trip).

 

The KH level is the buffer and is not all that high in this case, try using some crushed coral in the substrate or as a filter media to increase your buffering capacity. That will help stabilize your pH at a higher range and its completely safe.

 

Your profile indicates that your 10G tank is stocked with "4 female platys 1 male platy 1 cory cat" and has a slight amount of measurable ammonia. Is this still true?

What exactly are you ammonia, nitrite and nitrate levels now?

Also, are you using activated carbon? If so, when was the last time it was replaced?

 

The KH level is the buffer and is not all that high in this case, try using some crushed coral in the substrate or as a filter media to increase your buffering capacity. That will help stabilize your pH at a higher range and its completely safe.

I will most definitely try that tomorrow! Thank you!

Your profile indicates that your 10G tank is stocked with "4 female platys 1 male platy 1 cory cat" and has a slight amount of measurable ammonia. Is this still true?

What exactly are you ammonia, nitrite and nitrate levels now?

Also, are you using activated carbon? If so, when was the last time it was replaced?

The ammonia test shows a lighter color than the lowest amount on my indicator card (is that even possible with ammonia test?? maybe its the lighting in my kitchen). I do see the mistake now - that should read 0.
Nitrates and Nitrites are both zero as well.

 

The ammonia test shows a lighter color than the lowest amount on my indicator card (is that even possible with ammonia test?? maybe its the lighting in my kitchen). I do see the mistake now - that should read 0.
Nitrates and Nitrites are both zero as well.

Are you using the API kits? If so, try the nitrate test again, but beat the #2 nitrate bottle against a counter or table for at least a minute to mix the reagent thoroughly and get a valid test.

In a fish only tank, you have to have nitrates or your cycle is gone.

 

Are you using the API kits? If so, try the nitrate test again, but beat the #2 nitrate bottle against a counter or table for at least a minute to mix the reagent thoroughly and get a valid test.

In a fish only tank, you have to have nitrates or your cycle is gone.

I agree, sometimes the nitrate levels are low enough in a newly cycled tank that its hard to get a reading (or a very accurate one)

 

Good morning,

Along with the great info above, here is a link that may be helpful:


Please, do not use chemicals to alter your pH levels. They are unstable and will cause your pH to bounce around, possibly crash, and sudden fluctuations in pH can be fatal to your fish. (speaking from experience)

Ken

 

OK so I've got my pH stable now, however it is still low. At least it is not steadily dropping anymore. The crushed coral was finally delivered yesterday...how much should I put in the tank, and how long does it take to raise the pH? From what I've read, it raises pH very gradually. I can't seem to find any info on how much to add to my tank.

 

What is your current pH level? Do you know the GH or KH levels? These three components for a synergistic system that will constantly work to stay in balance.

As far as how much crushed coral, in only 10G it most likely won't take too much; but there really isn't a specific measurement we can give you. I would suggest you start with only 1/2 cup or less. Then, monitor your tank closely.

Place the crushed coral in a media bag/nylon stocking and add to your filter or place it next to your filter so it is in the water flow. Make sure you rinse it well to remove any residue to coral powder as that would cause a quick change and potentially affect your fish.

 

My tank has now completed cycling ( ) And two days ago I did a 75%+ PWC with my well water ( ) which has a pH of 6.6, which I am fine with. But today, the pH has dropped to 6.0? I have quite a lot of driftwood in my tank but I didn't think it would make such a drastic change. My substrate is Pool Filter Sand so it should be inert. Can anyone explain why my pH is dropping? Oh and I don't have a GH/KH test kit at the moment either.

 

A GH/KH test kit woud be most helpful. It would allow us to check the buffering capacity of your tank. A pH of under 6 will halt your cycle and allow ammonia and nitrites to start building again.

You might want to take out your driftwood for the time being and do another water change to bring the pH back up. It can be pretty dangerous to make adjustments to your water without being able to test and monitor reactions, so water changes to keep the pH up, would be best until you can get a GH/KH test kit.

Is this a planted tank? Yep. Just looked. The plants will use KH if other forms of carbon are unavailable to them, so this could explain why the pH has become low. Both the plants and the driftwood can have affects on KH and pH.

 

My tank has now completed cycling ( ) And two days ago I did a 75%+ PWC with my well water ( ) which has a pH of 6.6, which I am fine with. But today, the pH has dropped to 6.0? I have quite a lot of driftwood in my tank but I didn't think it would make such a drastic change. My substrate is Pool Filter Sand so it should be inert. Can anyone explain why my pH is dropping? Oh and I don't have a GH/KH test kit at the moment either.

Both the nitrification process and 'a lot' of driftwood' will acidify the water and cause a pH drop.

As tootsie stated, a GH/KH test kit is helpful .

Since you don't have fish in your tank, you can add a small amount of sodium bicarbonate (baking soda) to increase the pH as a temporary measure. Baking soda is considered riskier with fish because it can cause pH fluctuations.

Alternative is to add a small amount of crushed coral (calcium carbonate) to stabilize the pH. But this buffer may increase the pH to 7.5.

What is the tank size?

 

Did you let a sample of water sit for 24 hours before you tested the bore water pH? pH can be different when water is first drawn due to the presence of or lack of CO2 so it may come out of your tap at 6.5ppm pH and once it comes into balance with the gas in the surrounding atmosphere it could drop down to 6ppm by itself without the influence of driftwood, plants and any nitrification from the cycle. I wouldn't think this is the case since you've already managed to cycle the tank because you would have had issues with the cycle, but I thought it best to ask.

Sorry, I haven't been following your other threads. Maybe this was addressed in them.

 

GH, KH, and pH | 75315 | pH

https://www.fishlore.com/aquariumfishforum/threads/understanding-ph-kh-gh-in-home-aqauriums.113548/

Links of interest above.

Ken

 

ok thanks for the help guys I'll go get a GH/KH Test kit today from the LFS Here's what I mean by "A lot" of driftwood:


and

 

What time of day are you testing?

In a planted tank, it's good to test pH one hour before lights come on, and one hour after lights go out. You should find that the pH before lights on is lower than an hour after lights out. This natural fluctuation is typically of no concern to fish or the cycle.

 

@ I am testing In the middle of the day but is the natural fluctuation 0.6 or more pH?
Edit : thanks for merging the posts ryanr one was on my pc and the other on an iPod for pics but I didn't know how to edit on the iPod

 

Testing at the same time is important.

As to the swing, yes 0.6 is common, but more in medium to high tech tanks.

I'm guessing there's little buffering in the water (a lot Australia's water is very soft)

 

Ok so I went to the LFS and got the GH/KH test kit, and the tank's GH is 9 drops, but the KH is 0!!!:shock: like, put in drops until it turns yellow after blue, but it just goes straight to yellow!!! I will go and test the bore's GH/KH now
Edit: The bore's GH is 8-9 and the carbonate hardness is around 3
First drop water is blue, 2nd it turns clearish again and 3rd drop it is a light yellow.

What should I do??? what will my pH go down to if I don't get a hardener in there?

 

A KH of 3dkh isn't horrible, but I do prefer to see it about 4 or above for a planted tank. As I was telling you in my above posts, plants use KH as a source of carbon. The driftwood releases tannic acid, and the nitrification process as mentioned by Chunk101 both also have the ability to decrease KH because KH buffers the acids created in the tank. This is somewhat good news because you do have 3dkh in the well water and it is the activity going on in your tank that is leading to no KH.

Chunk101 has said in an above post that you currently have no fish in this tank. Is this still true?

 

Yes there are still no fish in the tank toosie.

 

That does make it easier for you to deal with. Because this tank is freshly cycled, I don't want you to do a gravel vac, but if you change about 90% of the water, you'll have a KH value in the tank again. Then you will need to start supplying a carbon supplement for your plants so that they no longer require the carbon your KH is made up of.

You can also opt to do Chunk101 's suggestion to boost the level up using a small amount of sodium bicarbonate (baking soda) instead of that large of a water change. Just add a little at a time to obtain the level you want. You will still need to start supplying the carbon supplement for the plants.

Or you can use ryanr 's recommendation in his post below. It sounds like a good one. If you opt to go with that, I'll let you two hash out any details, because I'm not familiar with this product. But I will watch and learn.

Initially, we want to raise the KH and pH of the water up quickly enough so that your cycle can start up again. (The no fish bonus.)

Now, at this point you have to make a few decisions.

#1.You can maintain the tank with your tap water's 3dkh, by supplying the plants an alternate source of carbon, and large weekly water changes of at least 50% or more to keep KH replenished, and monitor KH weekly until you get the feel for things. Then once or twice a month after you know it's staying stable enough.

#2.Or, you can opt to increase KH in the tank, but this means you may have to do adjustments on your tap water to increase KH and pH before you do large water changes once you have fish in the tank.

If you want a lot of driftwood in the tank, you will need to boost your KH some. A media bag with about 1/2 - 1 tbsp (to start out with) of Crushed coral, or crushed oyster shells placed in the filter will help replace and boost KH as well as boost pH. There are other products that can be used as well if there is a problem getting either of these products, but I prefer to start with one of these.

Monitor KH, and if need be, add more crushed coral (or whatever you're using) if KH doesn't increase as much as you would like, or if over time the KH starts dropping again.

Seachem Flourish Excel (or similar) is a product that provides plants with a source of carbon.

https://www.seachem.com/Products/product_pages/FlourishExcel.html

 

Hi, told you our water is soft! Here in Melbourne, tap water is about 3-4dGH, and 0-2dKH.

I use Seachem Acid and Alkaline buffers for my KH, Best thing I've used, as the alkaline buffer is phosphate free.

 

As per ryanr, our water in Australia is really soft. In Sydney our water is about 2-3 drops in KH test by API.

The 2 different solutions I have come up with for 2 different tanks.
1) 60 gallonplanted community. Seachem Aquavito Carbonate. This is potassium carbonate in liquid form from Seachem designed for planted aquariums. I use about 1/4-1/2 the reccomended dose every week followings water change. I use Seachem flourish excel as well for my carbon source. Keeps my pH stable at 6.8-7.2 and KH 3-4

2) 300g goldfish pond with plants. Given the expense of using a liquid substitute in such a larger body of water I opted for the crushed coral route as my pH was constantly dropping below 6.0. My LFS didn't have crushed coral but did have some coral skeletons that thy would sell to me. I got 3 pieces that were each the size of my hand. Crushed them to pieces about the size of a 50cent piece using a hammer against a large rock. Put the pieces in a mesh filter bag and added it to my filter. Since the. My pH holds steady at 6.8 and KH at 3

 

Alright guys today I got a bottle of Flourish Excel, so tomorrow morning I will do a big WC and start dosing that at half the recommended dose as per Machine11

 

Flourish excel you can dose at full strength as that is what the plants will use for its carbon source

 

Ah ok, that makes sense, thanks

 

Actually, after a large water change (over 40%) you have to add more as per the directions than a regular dose.
It was the potassium carbonate (Aquavito Carbonate) that I use 1/4-1/2 dose as per its instruction because I don't have a CO2 system

 

Okay, I have done a large water change (as close as possible to 100%) And added in the Flourish Excel. Current water parameters are: Ammonia 0.25ppm, pH 6.4, 9DGH, 3-4DKH, Nitrates 40-80ppm and Nitrites 0ppm. Adding ammonia now. Added ammonia to 4ppm

 

Forgive me (haven't been to bed yet, insomnia)... why are you adding ammonia? I'm sure I missed something lol.

 

To feed the BB @Mamajin, because there are no fish in there

**EDIT** Woot 100th post!!!

 

pH 6.4

To feed the BB @Mamajin, because there are no fish in there

Ok, I just wanted to be certain.

The cycle will either stall or fail if the pH is below 7. Once the cycle is stable with fish in the tank, it's ok if the pH falls below 7 (although you do want it to be stable).... just not while you're trying to cycle.

 

Okay todays results are in: pH 6.4, Ammonia 2ppm, Nitrite 0ppm, Nitrate 40-80ppm(looks darker than yesterdays), 2-4DKH and 9DGH. Ready for fish? Or wait it out a few days?

 

Wait it out until the bb converts the ammonia

 

The pH has dropped again What other explanations could there be?