Confusion on testing water quality, difficulty growing

[Dromna]

I'm somewhat new to planted tanks, or rather I'm new to caring for non-native water plants. I'm also new to testing water parameters. I have a tank that I inherited which is not growing plants very well (Tank 2), and I used aquarium coop test strips to look at the water parameters, but the color readout does not seem to be on the guide? 

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Do I have super high Ph water? Why is the buffer blue when the guide only goes yellow to green? Why is the hardness lavender when the guide only goes dark blue to dark purple?

For reference, Tank 1:

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Tank 2, where I recently lost a rubberlip pleco and plants have not been growing:

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Tank 3:

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I'd appreciate any help understanding the test strip results, and advice in general. For the plants in tank 2, I probably need more light? Some softer substrate?

[Seattle_Aquarist]

Hi @Dromna

Any possibility that there is a water softener on your water supply?  -Roy

[modified lung]

On 9/11/2022 at 9:20 AM, Dromna said:

 

  Reveal hidden contents

Do I have super high Ph water? Why is the buffer blue when the guide only goes yellow to green? Why is the hardness lavender when the guide only goes dark blue to dark purple?

Your pH does look super high. The buffer and hardness colors mean the levels in your water are above the strip's measurement range.

[Dromna]

Thanks @Seattle_Aquarist, @modified lung,

On 9/11/2022 at 12:16 PM, Seattle_Aquarist said:

Any possibility that there is a water softener on your water supply?  -Roy

Hi Roy! I live in an apartment in an area with hard water in general, and I expect that you are right and there is a water softener running. Are there common strategies to deal with this? I'll look around.

 

On 9/11/2022 at 1:32 PM, modified lung said:

Your pH does look super high. The buffer and hardness colors mean the levels in your water are above the strip's measurement range.

Oof haha, I guess so. I wonder what the GH and KH actually are then?

[Seattle_Aquarist]

On 9/11/2022 at 12:38 PM, Dromna said:

Thanks @Seattle_Aquarist, @modified lung,

Hi Roy! I live in an apartment in an area with hard water in general, and I expect that you are right and there is a water softener running. Are there common strategies to deal with this? I'll look around.

Hi @Dromna

The reason I asked was the extremely high pH, and the high level of alkalinity (aka carbonates) and if you were to use an API liquid dHG test kit you would likely find the dGH at "0" (zero).  A water softener removes calcium (Ca) and magnesium (Mg) from the water and replaces it with sodium carbonate.  This increases the pH, the alkalinity (dKH), and reduces the dGH (general hardness).  The high pH effects the plants ability to uptake of several plant nutrients such as iron.  In addition the plants need magnesium and calcium (both secondary nutrients) for healthy growth which the water softener has removed.  Lastly, the high amount of sodium (Na) added reduces the ability of the plants to uptake potassium (K)

Unlike a home owner you probably do not have access to water that is not going through the softener unless there is an outdoor faucet you can access.  If you do have a hose faucet take a sample of that water and test it and report back with the results.  Hope this helps! -Roy

[tolstoy21]

On 9/11/2022 at 1:16 PM, Seattle_Aquarist said:

Any possibility that there is a water softener on your water supply?

A water softener would (or should) result in blue for 'hardness', meaning 0-25ppm. At least this is my experience with those strips on water that has been run through a softener.

It is possible to have 'neutralizer' filter (looks just like a water softener, that boosts the Ph. But, these if installed correctly, should give a neutral to slightly basic Ph, something in the 7 - 7.8 range. The will show a super elevated Ph if the media (Calcite) has just been replaced, but this lasts a few hours or so and is typically flushed out in the AM after the first shower of the day.

So if there is any any kind of softener or water filter running and the levels are truly as high as strips show, then there is something seriously wrong with them. No one would target those levels intentionally in household water.

I would verify your strips results against another test kit, like the API drop tests. I use both the Coop strips and the API kit, and the don't always agree, but their readings should be close enough to one another.

[tolstoy21]

On 9/11/2022 at 4:11 PM, Seattle_Aquarist said:

A water softener removes calcium (Ca) and magnesium (Mg) from the water and replaces it with sodium carbonate.  This increases the pH, the alkalinity (dKH), and reduces the dGH (general hardness). 

I have yet to see a softener influence water Ph to any degree. 

In my experience, water softener media should only release sodium ions in exchange for Ca and Mg. This is why they are recharged with salt (NaCl), because during the recharge cycle the resin exchanges the hardness it's captured with the sodium ions that it's suddenly overwhelmed by via the brine solution. The dislodged Ca/Mg get flushed down the drain.

When the softener goes back into service, the resin does the opposite -- it exchanges a sodium ion for Ca or Mg, which is captured in the resin until it is flushed during the next recharge cycle. The sodium winds in your water, but to a negligible degree.

I use softened water in some of my tanks because I have high Gh in my well water. My well water has natural 0 Kh. After running through the softener, the Kh still remains at 0. 

Edited September 11, 2022 by tolstoy21

[tolstoy21]

@Seattle_Aquarist  Hmmm . . . I stand corrected. I guess sodium bicarbonate can be used in water softening as a method as opposed to ion exchange (the typical setup in most households). I wonder if something like an apartment building might go that route.

However, in the original test strip scenario. . . I would think if carbonate is being precipitated into the water in such a degree that it swings the Ph that high, the water should be very soft as a result.  At least in theory.  But, dunno.

Edited September 11, 2022 by tolstoy21

[modified lung]

On 9/11/2022 at 1:13 PM, tolstoy21 said:

A water softener would (or should) result in blue for 'hardness', meaning 0-25ppm. At least this is my experience with those strips on water that has been run through a softener.

This is also my experience. I've found the GH pad starts turning dark magenta at 150 ppm and gets brighter and pinker the higher the reading.

On 9/11/2022 at 1:27 PM, tolstoy21 said:

I have yet to see a softener influence water Ph to any degree. 

In my experience, water softener media should only release sodium ions in exchange for Ca and Mg. This is why they are recharged with salt (NaCl), because during the recharge cycle the resin exchanges the hardness it's captured with the sodium ions that it's suddenly overwhelmed by via the brine solution. The dislodged Ca/Mg get flushed down the drain.

Sodium carbonate softeners do exist and do raise pH. I don't think they are used very often in houses though. I think treatment plants use them if most of the hardness comes from Ca with very little Mg.

[tolstoy21]

On 9/11/2022 at 4:45 PM, modified lung said:

Sodium carbonate softeners do exist and do raise pH. I don't think they are used very often in houses though. I think treatment plants use them if most of the hardness comes from Ca with very little Mg.

Yeah I just realized this after I posted, and admitted my folly in a follow-up. My only experience is with the typical household softeners that use a standard brine wash regen cycle. 

In any event, I'd recommend @Dromna verify the results they are seeing by using an Api drop kit or another test method. (Trying to steer us back to the thread's original purpose so I don't accidentally hijack the thread!).  🙂

Edited September 11, 2022 by tolstoy21

[modified lung]

On 9/11/2022 at 1:50 PM, tolstoy21 said:

Yeah I just realized this after I posted, and admitted my folly in a follow-up. My only experience is with the typical household softeners that use a standard brine wash regen cycle. 

I saw that. I've never seen a sodium carbonate softener in person either. They are the bigfoot of water softeners.

Edited September 11, 2022 by modified lung

[Seattle_Aquarist]

Hi @tolstoy21

I am referring the most common type of water softener, the ones that use resin ion exchange and are recharged with salt (NaCl).  The output of the water softener contains high levels of sodium carbonate (NaHCO3) which has a pH of 8.3.  There are other types of water softeners such as reverse osmosis (RO), TAC (template-assisted crystallization),  and electric or magnetic softeners out there but the OP has the high pH and alkalinity associated with a resin ion exchange type of softener. -Roy

[tolstoy21]

On 9/11/2022 at 4:55 PM, Seattle_Aquarist said:

I am referring the most common type of water softener, the ones that use resin ion exchange and are recharged with salt (NaCl).  The output of the water softener contains high levels of sodium carbonate (NaHCO3) which has a pH of 8.3.

I guess this is possible. 

But to be honest, I run three different ion exchange softeners. One for my household water, one to remove nitrates from my well water for use in aquariums, and one to remove a bit of hardness for aquariums. All of these are regenerated with salt, and my resultant water has 0 Kh.  My household water passes through a neutralizer to intentionally boost the Ph so my water doesn't corrode my old copper pipes.  Without that, my water sits at about 6.4 Ph after aeration.  

I'll fully admit, I don't have experience with every softening solution there is (well, I do also run RO/DI), so I could be wrong.

Edited September 11, 2022 by tolstoy21

[Dromna]

Hi all,

On 9/11/2022 at 3:13 PM, tolstoy21 said:

verify your strips results against another test kit, like the API drop tests.

I don't have an API drop test kit, and it would take me a while to get one, but I might do so. You're thinking the GH/KH test set, or the reef master kit?

On 9/11/2022 at 3:11 PM, Seattle_Aquarist said:

If you do have a hose faucet take a sample of that water and test it

I don't know of an outdoor faucet, but it is raining currently, so I took a control sample from a puddle:

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This seems about what I would expect, so I expect that the test strips are fine.

On 9/11/2022 at 3:11 PM, Seattle_Aquarist said:

if you were to use an API liquid dHG test kit you would likely find the dGH at "0" (zero).

How does the API liquid dGH test differ, such that it would give a dGH of zero while the A-coop tests give a GHppm of >300?

[tolstoy21]

On 9/11/2022 at 8:14 PM, Dromna said:

I don't know of an outdoor faucet, but it is raining currently, so I took a control sample from a puddle:

If that's a sample from rainwater, then you're probably right, the strips are fine.

If you're getting 'softened' water through a functional water softener, your GH readings should be low to non-existent, looking the color that you see in your rainwater test.

With the original tank water samples you took and posted pictures for, did you take your readings after about one minute and not too much longer?

And I'm guessing your tap water returns similar results with the test strips?

On 9/11/2022 at 8:14 PM, Dromna said:

How does the API liquid dGH test differ, such that it would give a dGH of zero while the A-coop tests give a GHppm of >300?

They should give similar readings. If they didn't, and one gave 0 dGh while the other gave > 300 ppm, then one of the 2 test kits is from a bad batch.

On 9/11/2022 at 8:14 PM, Dromna said:

You're thinking the GH/KH test set

Yeah this is all you would need to confirm your readings.  But I think the rainwater test is ample confirmation that the strips aren't defective and working fine. 

Edited September 12, 2022 by tolstoy21

[Dromna]

Hi @tolstoy21,

On 9/11/2022 at 7:20 PM, tolstoy21 said:

did you take your readings after about one minute and not too much longer?

Yep. I didn't see noticeable color changes after the first ~30s though

On 9/11/2022 at 7:20 PM, tolstoy21 said:

I'm guessing your tap water returns similar results with the test strips?

The original test strip photo included a tap water control, which has similar GH/KH/pH to the tanks.

[tolstoy21]

I would say if your test strips are accurate (and they appear to be), then your water parameters is pretty much out of your hands without changing your water source.

Hopefully this is just some passing anomaly in the larger water system.