High PH, Low KH. Suggestions?

[GeorgieGirl1028]

Hi All!

I’m having an issue with high PH & low KH causing fluctuations. We have city water & the PH varies between 7.8-8.2 (after sitting in an open bucket for a couple hours.) The GH is consistently either 10-11 drops. The KH varies but is usually between 1-4 drops.

I have guppies & no plants at this time (with the exception of a couple moss balls.)

I have been using Seachem Neutral Regulator because it was recommended by my local fish store. They keep their guppies in 7PH. The Regulator has helped increase the KH to between 4-8 drops. However, when I test tank water it is usually 7.2. The last two days it has crept up to 7.4 for some reason.

Does anyone have any suggestions on what I can do to increase buffering capacity without raising the PH or GH anymore? I’d like to only use Prime for each water change & lose the additives. Is this possible? I’ve experimented with crushed coral & baking soda in the past.

 

[Byron]

The first thing is to determine what if anything the municipal water authority is adding to affect pH. Do you know the GH of the water? KH is 1 to 4 dKH. What is the pH according to the authority, and according to your tests? I know you give the pH at various times, but i want to pin this down more. When testing tap water for pH you must ensure any dissolved CO2 is out-gassed as this will affect the test. Let a glass of tap water sit 24 hours, then test pH.

Crushed coral is not a good buffer because it is calcium only. Baking soda is dangerous long-term for fish so this is not advisable. There are ways to do buffering, but first let's make sure we understand the above. The GH/KH/pH are inter-related and the whole package has to be considered or it can make life for the fish very difficult.

 

[GeorgieGirl1028]

GH is always 10 or 11 drops both from tap & in tank. (I forget the conversion.) I’ve done daily testing on both tank & tap water for almost 6 weeks now. I also experimented with testing the tap water after letting it sit in a 5 gallon open bucket for different amounts of time. I tested right after it came out of tap, 30 mins, 1 hour, 2 hours, 4 hours, 8 hours, 16 hours, 24 hours, & 48 hours. The parameters don’t seem to ever change any after about 2 hours. When it comes out of tap the ph is definitely much higher.

When you say find out what my municipal water authority is putting in the water what am I looking for? I found some information. I’ve tested it for ammonia, nitrites, & nitrates & it’s always zero. On two occasions I have gotten what may look like a bit of ammonia but not quite dark enough to be a true .25ppm.

 

[Essjay]

What brand is the tester? With most of them, 1 drop = 1 dH, but there are some makes are different.

 

[Byron]

I also experimented with testing the tap water after letting it sit in a 5 gallon open bucket for different amounts of time. I tested right after it came out of tap, 30 mins, 1 hour, 2 hours, 4 hours, 8 hours, 16 hours, 24 hours, & 48 hours. The parameters don’t seem to ever change any after about 2 hours. When it comes out of tap the ph is definitely much higher.

Can you give us the numbers here? I know you may have done this above, but it helps us to see everything in one place. The last sentence, is this accurate, that the pH is "x" in the tap water initially and then lowers as the water sits?

 

[GeorgieGirl1028]

What brand is the tester? With most of them, 1 drop = 1 dH, but there are some makes are different.

It’s just the API liquid tests for Ammonia, Nitrite, Nitrate, PH, GH, & KH.

 

[GeorgieGirl1028]

Can you give us the numbers here? I know you may have done this above, but it helps us to see everything in one place. The last sentence, is this accurate, that the pH is "x" in the tap water initially and then lowers as the water sits?

Absolutely. Do you mean what is the PH before I put in tank & after?

After the water sits (for a couple hours) it is usually anywhere between 7.8-8.4PH. The GH is always either 10 or 11 (both in tank & before.) KH is anywhere from 1-4dKH before I add the Neutral Regulator. After Neutral Regulator the PH drops to 7 or 7.2 & the KH increases to anywhere between 4-8dKH. There is no ammonia, nitrite, or nitrate in tap water. (With the exception of twice I got a reading of .25 or lower for ammonia before adding it to tank.) Last night the PH was up to 7.8 when in the morning it was 7.2. I lost one of the 4 guppies in the 10 gallon. No signs of illness so i’m assuming it was caused by the massive water change & shift in PH. The others seem stressed. Swimming near surface or in place mid tank.

 

[Byron]

GH and KH will usually remain much the same from source (tap) water to aquarium water. If you were specifically targeting these, they would vary. For example, if you had calcareous substrate or rock it would tend to dissolve calcium and magnesium and increase GH/KH. Alternatively, if you diluted the source water with "pure" water (RO, rainwater, etc) is would lower the GH/KH proportionally. The Neutral Regulator is targeting the KH [I'll come back to this].

The pH will adjust itself according to these, as well as dissolved CO2. The pH is buffered by the GH/KH and will resist changes according to the buffering capacity. If the KH is as low as it seems, the buffering willnot be substantial so the pH will tend to lower as the organics accumulate and are broken down by bacteria, releasing CO2 which creates carbonic acid, thus lowering the pH.

There is also a diurnal pH adjustment. This is especially evident in tanks with live plants. As the plants use the CO2 for photosynthesis during the daylight, the pH rises. During the night darkness, CO2 rebuilds and the pH lowers. This is one reason for always testing pH at the same time of day, if you want to get an idea as to what it is doing long-term. This also occurs in natural waters, and fish have no difficulty. It is not usually more than a couple of decimal points. This brings me to the pH shift causing the death of the guppy...I would say very unlikely. Fish can actually manage a muchg larger pH shift provided it is not sudden, and the diurnal or similar fluctuations here are not going to cause them trouble. Most biologists suggest that a pH adjustment of under 1 degree (meaning, from 6.5 to 7.5 etc) is not problematic if it is over a 24-hour period.

To the Neutral Regulator, I would discontinue this. It really is not needed, and the biological chemistry will be more stable without it. It also gets inside the fish and any substances that are not absolutely essential should not be used. Water, along with every substance dissolved in it, continually enters the fish via osmosis through every cell, into the bloodstream and internal organs. Best avoided.

There are natural ways to buffer pH. I used dolomite for several years; just half a cup in a nylon filter bag raised the pH from 5 to 6.5 and it never varied. But you do not have acidic pH to begin with, so there really is no reason to adjust it. Fish suiteed to your water's GH are also suited to a basic pH (above 7.0) and that is really all that matters. If you decide to stay with livebearers or similar fish requiring moderately hard or harder water, increasing the GH/KH/pH would be advisable, and here you can use a calcareous substrate and/or mineral salts made for rift lake cichlids. Never marine salt mixes, which also contain common salt, sodium chloride, and this is detrimental to all freshwater fish to varying degrees.

If you decide to move to more soft water species, the GH is OK for many of them, and I would let the pH again do what it wants naturally.

I always advise keeping things as simple as possible. An aquarium functions solely according to the laws of nature concerning biology and chemistry. Every interference we introduce upsets those natural processes, and it is not always easy to predict the ramifications. This is why chemical substances should only be used if essential, and then only as little as necessary. You mention Prime, and the foregoing is why I do not recommend this conditioner, unless you have ammonia/nitrite/nitrate in the source water. There is no need to be adding chemical concoctions that impact these natural processes; the system will be less stable and the fish will be impacted from the chemicals if not more.

 

[GeorgieGirl1028]

That was my problem before I started using the Neutral Regulator. The KH out of tap is so low that any acids in the tank seem to eat it right up. My KH would go from 4 one morning to 1 or zero the next. Once the KH was used up (usually with a day or two) the PH would tank drastically to 6.2 or 6.4. That’s where the Regulator came into play. It at least kept the PH stable.

My PH & GH from my understanding are good for guppies. It’s just the low amount of KH that makes my PH unstable. I would love to get rid of the Neutral Regulator & just use Prime to condition the water but I don’t know how to keep my KH from dropping so low without doing daily water changes.

Should I be measuring dissolved oxygen too?

 

[GeorgieGirl1028]

I should mention I test the water every morning but last night because the fish were staying at the surface or swimming in place in the middle of the tank & haven’t been eating for two days I tested the water in the evening. It was 7.2 that morning but had spiked during the course of the day to 7.8. Nitrates went up from 5ppm to 20ppm also. So I did a 75% water change hoping that would help. By morning one guppy had passed & the others still seem not well. I don’t see any other physical indicators of disease or injury in any of the fish that’s why I assumed the culprit must be the shifting water parameters.

 

[Byron]

That was my problem before I started using the Neutral Regulator. The KH out of tap is so low that any acids in the tank seem to eat it right up. My KH would go from 4 one morning to 1 or zero the next. Once the KH was used up (usually with a day or two) the PH would tank drastically to 6.2 or 6.4. That’s where the Regulator came into play. It at least kept the PH stable.

My PH & GH from my understanding are good for guppies. It’s just the low amount of KH that makes my PH unstable. I would love to get rid of the Neutral Regulator & just use Prime to condition the water but I don’t know how to keep my KH from dropping so low without doing daily water changes.

Should I be measuring dissolved oxygen too?

I mentioned the safe way to deal with the KH and pH in my last post. Neutral Regulator is not it, as it impacts the fish and messes with the natural chemistry. Dolomite was what I used in the 1990's, but more recently I have had the same results with aragonite. Two or three tablespoons in a bag in the filter of a 90g tank raised the pH from 6 to 7.6 and kept it there for years. And I do 60% water changes with the soft water every week. Aragonite works, crushed coral does not, because the aragonite is calcium and magnesium.

I wouldn't worry about oxygen, unless there are signs of low oxygen. Surface disturbance handles this.

 

[GeorgieGirl1028]

I mentioned the safe way to deal with the KH and pH in my last post. Neutral Regulator is not it, as it impacts the fish and messes with the natural chemistry. Dolomite was what I used in the 1990's, but more recently I have had the same results with aragonite. Two or three tablespoons in a bag in the filter of a 90g tank raised the pH from 6 to 7.6 and kept it there for years. And I do 60% water changes with the soft water every week. Aragonite works, crushed coral does not, because the aragonite is calcium and magnesium.

I wouldn't worry about oxygen, unless there are signs of low oxygen. Surface disturbance handles this.

Thank you so much for your continued responses. I certainly appreciate your help. You have been very informative. Please forgive me, I don’t believe I’m understanding correctly. If I use aragonite or dolomite won’t that raise my already high ph even higher?

 

[Byron]

Thank you so much for your continued responses. I certainly appreciate your help. You have been very informative. Please forgive me, I don’t believe I’m understanding correctly. If I use aragonite or dolomite won’t that raise my already high ph even higher?

Probably. But you need to experiment, by which I mean start with very little and see what follows. I would only use maybe half a tablespoon of aragonite in a small nylon filter bag; you can hang this in front of the filter return, or place it inside the filter if it is a canister or similar. It doesn't mess with the GH. And if you are intending livebearers or similar moderately hard water species, a higher pH is not an issue.

 

[GeorgieGirl1028]

Ok I’ll give this a try & see how it goes. Thanks again for all your helpful advice!