# Will plants get rid of potassium from water softener?



## Scottso (Oct 2, 2009)

Potassium is great for plants. The problem is that softened water replaces almost ALL of the calcium and magnesium in the water with potassium. Plants, fish and snails need the calcium and magnesium as well to survive. This is why softened water is not really good for aquariums.

I'm assuming you are using potassium chloride in your water softener. If you are using sodium chloride then you are actually replacing all the calcium and magnesium with sodium. 

I've never heard of potassium killing snails, though. I add a lot of potassium as part of my plant ferts, but then I'm sure I don't have nearly as much potassium in the water as you have. Are you sure there isn't some other factor causing issues?


----------



## MidnightSkies (Feb 3, 2009)

I've never had a problem with any fish, aside from when our carbon treatment hadn't been replaced. Fish have always thrived. Invert however have done quite the opposite. Snails will stay tucked tightly inside of their shells instantly until they end up dying. This has been going on for years. I was hoping maybe it was something else was fixed now, but I was wrong. Potassium is the only problem left. I've ruled out everything else my simply a process of elimination. There have been a select few that have had the same problem with potassium in their water softener, but it doesn't look to be very common. I guess we just have extremely hard water. I believe it was when we were using sodium that snails were actually thriving, and as soon as we switched years ago, an entire tank full suddenly died. 

I'm not sure how much potassium plants actually take up, especially low light plants. I'm hoping that it would be enough to at least make it safe for inverts. I'm really in need of MTS to help with my sand and possibly a little algae. Would low light plants use up a large amount of potassium? Is there anything that would absorb potassium from the water?


----------



## wkndracer (Mar 14, 2009)

Dry plant tissue analysis published by Edward on his PPS systems put Potassium at 27% by weight. Diana Walstad's book implies a similar number. 
The ion exchange of the water conditioner resins does not transfer whole molecules of either sodium or potassium in the process. I use an RO system following my whole house water softener (salt regen) for tank use and still struggle / search for the complete answer. 
Plants, fish and inverts do very well in my tanks for a time but Briggs failed twice after about 6-8 months in the tanks so something is missing or out of balance. I've spoken with several lab technicians in the boiler chemistry field and three degree carrying chemists without answer.
Pre-treated well readings;
Ph 7.2
kh 196.9 ppm
gh 179 ppm
phosphate 1.0
iron (off the scale) Hagen Nurtafin test kit.
Nitrate, Nitrite, Ammonia 0.0
Water treated through my Kinetico RO system tested w/API drops (uses salt for regen);
Ph 7.0
kh 196.9
gh 35.8
phosphate .75
Nitrate, Nitrite, Ammonia 0.0 (drop tests don't register the sodium)
The following were tested results at my work location water lab;
Temperature 25°c
pH 7.56
hardness 10 ppm
iron 0 < .1 ppm
Maximum Turbidity 1.0 NTU
Maximum Chlorine .02 not visible

Prior to adding the RO system while the numbers shifted on tested results the water TDS was basically the same. The filters only removed suspended solids and the dissolved solids total remained the same with sodium ions exchanged for Calcium, Mg and Fe.

Fast growing plants like duckweed, sunset hygro and swords are nitrate and potassium hogs but I don't know if they're filtering effect on the water column is fast enough to polish out imbalances for the animals. 
I feel like my issues keeping inverts revolve around a mineral deficiency in the water reconstitution after it's striped by the RO.

I hope someone posts in with an answer for both of us.


----------



## queensalmon (Oct 15, 2008)

This is a great question that I will follow carefully. I have had the exact same issues. Our well water is hard enough to stand on. Have used potassium for ten plus years and was never able to keep shrimp or snails - never. Always suspected copper (very old well and pipes were all copper - holding tank too). This fall, moved the well ten feet - built new house with pvc pipes etc. Thought I'd try a few shrimp and snails - no losses. B
UT we also had to switch from potassium to sodium at the same time. Local vender said that potassium pellets had jumped to 4 times its price due to the new concentration of use in China as a fertilizer. Oh, ok, whatever. So sodium it is now. Bypassing the softened water is not an option as the water is permanently orange - stains the tank, plants etc. Never clears. So, is it the potassium - the copper - or does sodium remove the copper? 
Thanks for asking this - can't wait to hear what others find.

Queensalmon


----------



## MidnightSkies (Feb 3, 2009)

I'm so glad to see that I'm not the only one having this problem! I've posted similar questions on multiple forums, just to have people tell me potassium doesn't cause a problem and continually ask if I treated my (brand new just set up, no even any fish yet) tank when I had answered the question multiple times. People drive me nuts sometimes. 

My parents built the house about 6 years ago, so it is a brand new house. According to my know it all mother it's IL law that you have to use copper pipes. I'd have to ask my dad to know for sure. Since I have kept snails very well here previously, that also leads me to believe it's not copper. A few times we have used sodium rather than potassium, especially when we first moved, and I'm guessing that's when the snails lived. 

An RO unit will be bought at some point in the future, but not anytime soon. Lugging 5 gallon jugs around the house is also something I really want to avoid. I'm in an area that regularly floods, and the combinations of everyone have septic tanks, farm field run-off, and disgusting ponds, put a whole lot crap (literally) in our water that needs to go through the rest of the treatments. I'm left with no other options really. Today I'm going to very slowly see if I can acclimate some snails to my tap water, and try to figure out what percentage of my tap water I can use when mixed with distilled.

I think I might fork out the money to get a good deal of low light plants off of here, and definitely a good portion of floaters and see if the plants will actually use up enough of the potassium. First on the list to try and figure out how to work pay pal, haha! 

If any of you come up with any ideas, I'm willing to try just about anything here as long as it won't cost me too much (unemployed). I'll keep everyone updated as time goes on as well.


----------



## Wasserpest (Jun 12, 2003)

Could you bypass the water softener? Get the water directly from the well?


----------



## Diana (Jan 14, 2010)

If you find that plants work (they probably will) then set up 2 tanks. 
The first tank has lots of plants, and the best light you can arrange. Emersed growth of the plants would be optimum, or else supplement with CO2. 

Fill this tank with the best water you can, perhaps a blend of tap and filtered. (gotta test a few recipes, see what works the best)
After the plants have worked on this water for several days or a week, then use this water to set up a shrimp and snail tank. 
Refill the plant tank with tap and well water and use this water for water changes when the plants have done their best. Keep the shrimp and snails in a planted tank, too. 

If you can find a reliable potassium test I think that it would be really useful for you. 

Another option:
Set up a tank (not aquarium tank, perhaps a garbage can) with well water. Run a canister filter on it. Put into the canister filter all the filter media you need to prepare the water for an aquarium. Skipping the potassium treatment from your filter. You might look into those resin pads that soften the water, remove phosphate, copper and many other things. Activated carbon, perhaps a micorn floss for particles. Peat Moss can also be part of the system. A more complete laboratory test of the raw well water might guide you here. What exactly is in the well water, and at what levels? Is it something that you need to filter out, and to what degree? These are the questions that I would ask. You would need to set up the system, then test each filter media to see how effective it is, and how long it lasts. 

There are 4 pages of chemical media listed here:
http://www.bigalsonline.com/BigAlsUS/ctl3684/cp18423/cl0/chemicalmedia?viewType=Category
Granted, a lot are aimed at nitrogens, which may not be a problem (planted tank will remove these), but skim through and see all the other things you can remove from the water with the right media. 

A friend's well (agricultureal area) tests over 10 ppm NO3, and hardness (GH and KH) off the scale. They do not keep fish.


----------



## plantbrain (Dec 15, 2003)

wkndracer said:


> Dry plant tissue analysis published by Edward on his PPS systems put Potassium at 27% by weight. Diana Walstad's book implies a similar number.
> 
> I hope someone posts in with an answer for both of us.


If, that is if, they stated that is the dry weight 27% for K+, they are wrong(Diana did not report this BTW in her book).

K+ is typically 1, maybe 2% for aquatic plants. Various aquatic plant species are widely available on line for ppm and % dry weights. See references below.

The person referenced by Diana, Gerloff, has a paper widely available:

http://www.new.aslo.org/lo/toc/vol_11/issue_4/0529.pdf
The 1975 book is not easy to get a hold of. 
8000 mg/kg does not translate to 27% dry weight.

8 g/1000g = 0.8% for critical concentration, and 4.5% for her plant references.

Reddy covers a more review based approach to K+ in aquatic plants.

http://wetlands.ifas.ufl.edu/publications/PDF-articles/161.Influence of potassium.pdf 

1% to 8% in one of the highest K+ dry weight aquatic plants.
1-2% is a typical range, and with more N and P, there's more K+ uptake.

If you limit the other factors, like light, CO2 or other nutrients, then it can have a reducing effect on K+ uptake.

20-50ppm are typical ranges of K+, NO3 is often in the 20-50ppm ranges, P at 2-4 ppm ranges for their non limiting growth solutions.

This is typical for EI dosing:icon_cool
EI is suppose to be non limiting for nutrients, only then then can you look at factors independently. This way you have a reference to compare to.
If you limit say CO2 or other nutrients, it makes the results confounding.

Each species will also have their *own ranges* of ppm's that's optimal.
Non limiting is somewhat easy to target if you have a community of various species, limiting concentrations in a community of different species will have a lot more competition interactions between different species.
This is much harder to target and find the right range for every species in the tank.

This is also true for light and CO2 as well as nutrients.

So rather than trying to figure heads or tails and all the possible variations, I go higher for CO2/nutrients and find non limiting for the weakest most prissy wimpy plants that are the poorest competitors.

If they do well, then the rest of the strong competitors surely will. This is not unreasonable logic. 

Regards, 
Tom Barr


----------



## lainealex (Sep 27, 2009)

I have a potassium chloride softener, and after ruling out every other possible problem I came to the conclusion that the potassium chloride was killing not only every single invert I tried, within a few hours, but also, slowly but surely, all my plants! I went through three rounds of planted tanks divided into six tanks before I figured out what was happening. My feeling is that the way the potassium in the softener salt works, it somehow dehydrates the cells of the inverts and plants - this is the conclusion the research I did led me to. You can dose other types of potassium obviously, and there are no problems. But this PC from the softeners is lethal. I could not keep even the most simple and impossible to kill plants alive for more than a few months. Things like crypts and hygros - even moss balls were dying! 

Much to my total horror, I switched to RO and within a week everything was fine. I don't even use my tap water for rinsing off my plants or my frozen foods now.

A final note: I talked to the owner of Greenleaf Aquarium and he told me that he won't install aquariums in houses with PC softeners - he simply turns those people away unless the switch to RO. He's done it, and had the same results the rest of us have had. 

Lainey


----------



## wkndracer (Mar 14, 2009)

plantbrain said:


> If, that is if, they stated that is the dry weight 27% for K+, they are wrong(Diana did not report this BTW in her book).
> Regards,
> Tom Barr


Edward's PPS papers do indeed state 27% as a dry plant tissue analysis. Volume 2, Issue 1, page 1.
Nitrates Phosphates and Potassium the NPK Relationship
K 27% PO4 14% NO3 59%
If his information is wrong, I'm good with that. 
I also did post that Diana Walstad's book implies a similar number. 
p.105"..'aged' aquarium water contains much higher concentrations of nutrients than most natural waters. In aquariums then, one would expect the water to become a major nutrient source for plants. 
Table VII-2. Nutrient accumulation by My Aquarium Plants. The 'Critical Concentration' of each element are published values for _Elodea occidentalis._ 'Elements Found in My Plants' is from a chemical analysis by the North Carolina State Agronomy laboratories. Numbers represent the average of 3 separate analyses of healthy miscellaneous stems/leaves from 3 of my aquariums."









Quoting the highest concentration listed was for K. Higher even then N running second in volume.
Whether Edward is wrong or the math doesn't correspond between Ms. Walstads data in mg/kg and Edwards in percentages the statement I made was very broad in term but stated similar in number with or without error. I did not state Ms. W reported this in her book but something similar.

Similar to me is the two largest mineral contributors being nitrate and potassium.

OP, I still don't see our answer anywhere here. Out of my house water softener TDS reads 207ppm and out of the RO unit the TDS meter reads 3ppm so sodium or any other mineral at 3ppm I don't feel like there is much left here to be toxic to inverts before rebuilding with GH booster.

Again, I hope someone posts in with an answer for both of us.


----------



## MidnightSkies (Feb 3, 2009)

I have to admit that a lot of this is going over my head. Maybe I should have stuck with my second chemistry class... Then again what fun is chemistry when you can't experiment? I'm also a complete planted aquarium noob, so forgive me. This was 'supposed' to be my first planted tank.

Wasserpest- As I stated, I live surrounded by farm fields and in an area that regularly floods. The water is toxic to even fish if I bypass all of our other treatment procedures. Plus I believe that the water is so full of calcium that all of my equipment would probably be junk in two weeks. 

Diana- That method does sound like it would really work. If I had the money and the space I would definitely try that, and I would like to test it one day. Sadly though, it seems like it would cost more than an RO unit, and I live with my parents so space is next to none at the moment. That is something that I would really like to try however. 

I do have a TDS meter and just tested the water... 400! Last summer I remember it being in the 300s. The water regularly also read either 'soft' or 'very soft' so that's a very large amount of potassium hanging out in my tap water. 

Is there a difference when it comes to plants absorbing potassium between potassium chloride and potassium phosphate? After lainealex's post I'm worried that I'll spend all the money for plants to see how they do and end up wasting all that money. I'm currently in a very tough place in life money wise, so I really don't want to risk that much. 

I did do a little test yesterday with how much of my tap water a snail can live in with distilled water added in. Turns out that between 1/4 and 1/3 of my tap water with the rest being distilled should be about right, but I don't know if that would work long term. Anything more than about 1/3 had the snail losing a lot of mucus and eventually hiding in its shell. At that point, back in his tank he went with his buddies and after a while he was perfectly fine. That really doesn't give me much to work with though. If I have to use that little I might as well just skip using my water all together. Looks like I will be trying to rehome these snails so I can get my water problems worked out. RO unit is sounding better and better...


----------



## plantbrain (Dec 15, 2003)

wkndracer said:


> Edward's PPS papers do indeed state 27% as a dry plant tissue analysis. Volume 2, Issue 1, page 1.
> Nitrates Phosphates and Potassium the NPK Relationship
> K 27% PO4 14% NO3 59%
> If his information is wrong, I'm good with that.
> ...


I'm not checking his drivel.........Diana and myself at least cite things for support :thumbsup:

I do dry weight tissue analsysis and have done so for sediments, and many species of aquatic weeds.

I can assure you, there's no way it's anywhere near 27%, all you have to do is look up some references, I cited several for you:thumbsup: 

Her % are correct and within standard ranges for tank grown plants with plenty of excess/ non limiting dry weight tissue mineral nutrients.
They are NOT similar to his claims.

Hyacinth has the highest % K+ of most any aquatic plant known.
8%. + This is way beyond the critical amounts. I listed the citations here for you to read. 

N and K+ can be similar, or they can be 1 to 10 ranges, or 5:1 ranges even without too much issue. KNO3 adds about 4X more K+ relative to the demand for N, so unless 75% or more N is coming from sediments and fish waste, there's not much need to add more, but doing so does no harm till you get to salt stress levels. I still add more, about in the 30ppm range average from KH2PO4/K2SO4.

See Reddy above.



> OP, I still don't see our answer anywhere here. Out of my house water softener TDS reads 207ppm and out of the RO unit the TDS meter reads 3ppm so sodium or any other mineral at 3ppm I don't feel like there is much left here to be toxic to inverts before rebuilding with GH booster.
> 
> Again, I hope someone posts in with an answer for both of us.


K+ and Cl- at higher levels, 200-400 TDS is fine.
Floating plants will scrub out most all nutrients (not just K+) more than most submersed species. By offering citations, we can look into it more and then you run less risk of misinformation and learn more about the topic.

Not a bad way to do it.

Regards, 
Tom Barr


----------



## plantbrain (Dec 15, 2003)

MidnightSkies said:


> I have to admit that a lot of this is going over my head. Maybe I should have stuck with my second chemistry class... Then again what fun is chemistry when you can't experiment? I'm also a complete planted aquarium noob, so forgive me. This was 'supposed' to be my first planted tank.
> 
> Wasserpest- As I stated, I live surrounded by farm fields and in an area that regularly floods. The water is toxic to even fish if I bypass all of our other treatment procedures. Plus I believe that the water is so full of calcium that all of my equipment would probably be junk in two weeks.
> 
> ...


I think you are okay if the TDS is in the 300 range.
You might cut with 1/3 to 1/2 RO if you go that route.

TDS for Vals, Hydrilla, Pondweeds, admittedly tougher salt stress plants grow in 1-2% salt water, 1300ppm Cl-, see Salt Springs Florida.

Lightly softened water is okay when using KCL as the softener salt.
Heavily softened, maybe not.

Still, going with a cut of % for RO water is not a bad idea if the system cannot be by passed. NaCl is quite another matter.
Sodium is a lot more problematic for plants.

Regards, 
Tom Barr


----------



## Arv (Oct 3, 2011)

plantbrain said:


> Lightly softened water is okay when using KCL as the softener salt.
> Heavily softened, maybe not.
> 
> Regards,
> Tom Barr


I use a KCL water softener and per my water utility's website my tap water entering the house is 33mg/L or 1.93 gpg GH. So it this considered lightly softened water?

the new growth on my swords are curled, but not all of them, and from what I've researched this could indicate the lack of calcium which the high amount of K could be blocking calcium intake or I don't have enough calcium and magnesium since K has replaced it from softening. the java ferns don't seem to be growing, the anubais are growing a leaf maybe every 10 days but some of the older leaves are getting one or two yellow spots. My API GH test is kinda hard to read since the color is so light. I don't even see it turning orange just a yellowish tint with the first few drops. 

Been dosing Flourish for about a month, and just placed some tabs and started dosing KN03 and KH2PO4 about 2 weeks ago. 

Thanks!
Raymond


----------

