The effects of a whole house Water Softner

[Matt77]

Hello,

 

Wanted to get some feedback about the affects of a whole house water softener on tropical plants and fish.  It is obvious that the main change will be the hardness of the water, however online research has indicated some potential issues with how the water softener softens the water (Basically exchanging ions of different elements).  The problem is the "salt ions" left in the water?  Again, the water is fresh water, but softened with salt.  Online research has conflicting information and none of the big names in YouTube really have touched on it.

 

Thanks

[Eric R]

Have you been able to test the water before and after the softener to see what water parameters you have?

[lefty o]

there is virtually no salt transferred from a water softener to the water. the salt is used in flushing the resin tank, the resin is what removes minerals/hardness from water. if the trace amounts of salt bother you, all water softeners have a bypass valve on them.

[OnlyGenusCaps]

2 hours ago, Matt77 said:

Hello,

 

Wanted to get some feedback about the affects of a whole house water softener on tropical plants and fish.  It is obvious that the main change will be the hardness of the water, however online research has indicated some potential issues with how the water softener softens the water (Basically exchanging ions of different elements).  The problem is the "salt ions" left in the water?  Again, the water is fresh water, but softened with salt.  Online research has conflicting information and none of the big names in YouTube really have touched on it.

 

Thanks

Water softeners exchange Calcium for Sodium (largely, but there are other lesser ions exchanged, and you could use potassium salts instead at a higher cost).  Sodium is a 1+ ion and Calcium a 2+.  You'll be getting two atoms of sodium in your water for each calcium atom removed.  Basic chemistry.  If you water is really hard, you could see some salinity. 

That said, if you are really concerned, you could get a salinity test/refractometer to be certain. Always good to test the water.  Then you can be sure.

[lefty o]

https://www.water-rightgroup.com/resources/myths-about-water-softeners-8-things-people-get-wrong/

[OnlyGenusCaps]

Right.  Sodium in your water.  That's what I am sating.  And the link admits to that.  Arguing it's not "salt" because it is not NaCl is a cute little industry trick.  But, yup, you'll get sodium in your water.  Could be sodium carbonate, which is still a salt. 

[Eric R]

We don't run our softener, so I don't personally have experience with using water from a softener in my tanks. Enough people have done it without noticeable ill effects that it's probably not an issue. Sensitive fish could potentially have a reaction to the trace amounts of sodium left over after the softener. Two non-industry sources have the following to say about sodium levels of softened water:

"The exchange of hardness minerals for sodium adds 7.5 milligrams per quart for each gpg of hardness removed." -PennState Extension

"Softened well water in our area on average contained a 2.5-times-higher concentration of sodium than local municipal water, comparable with previous reports." -Archives of Internal Medicine

Here's some information from Practical Fishkeeping on the effects of salt on fish.

I think the bigger issue is that shrimp, snails, and plants all need the elements removed by water softeners, which are calcium, magnesium, and iron, so what you will likely need to do is add these back into your water for your aquariums if you do use water from your softener.

I would recommend testing the water before and after your softener for kh, gh, ph. If the pre-softener water isn't too hard and doesn't have a ton of iron in it, I'd recommend figuring out a way if you can to use the unsoftened water for your aquariums.

 

Edited April 23, 2021 by ererer

[lefty o]

4 hours ago, OnlyGenusCaps said:

Right.  Sodium in your water.  That's what I am sating.  And the link admits to that.  Arguing it's not "salt" because it is not NaCl is a cute little industry trick.  But, yup, you'll get sodium in your water.  Could be sodium carbonate, which is still a salt. 

yes you get some salt, trace amounts. thats it.

[Fishdude]

You get more sodium the harder your water is. I've spoken to some folks for whom softened water was a problem for plants but not a problem for the fish. The water coming from my tap is basically liquid rock because it originates in a limestone aquifer, so we'd have more sodium than I'd like in my aquarium water.

You can also exchange the sodium for potassium if you feel like spending an absurd amount of money. I just opted for an RO filter as a way to cut my water from the street (rather than remineralizing with Seachem).

[lefty o]

lets not miss the point people, all water softeners have a bypass valve on them. dont want soft water in your tank, push the bypass valve. dont want all your piping, faucets, and shower crusty, put the valve back so you get soft water. i just dont get why this is an issue, as even with a water softener in your home, if you dont want softened water in your aquarium, you dont have to.

[Fishdude]

3 hours ago, ererer said:

We don't run our softener, so I don't personally have experience with using water from a softener in my tanks. Enough people have done it without noticeable ill effects that it's probably not an issue. Sensitive fish could potentially have a reaction to the trace amounts of sodium left over after the softener. Two non-industry sources have the following to say about sodium levels of softened water:

"The exchange of hardness minerals for sodium adds 7.5 milligrams per quart for each gpg of hardness removed." -PennState Extension

"Softened well water in our area on average contained a 2.5-times-higher concentration of sodium than local municipal water, comparable with previous reports." -Archives of Internal Medicine

Here's some information from Practical Fishkeeping on the effects of salt on fish.

I think the bigger issue is that shrimp, snails, and plants all need the elements removed by water softeners, which are calcium, magnesium, and iron, so what you will likely need to do is add these back into your water for your aquariums if you do use water from your softener.

I would recommend testing the water before and after your softener for kh, gh, ph. If the pre-softener water isn't too hard and doesn't have a ton of iron in it, I'd recommend figuring out a way if you can to use the unsoftened water for your aquariums.

 

Hey it's Penn State Extension! Woohoo!

[KaitieG]

If it helps at all, we have a whole house softener (super hard water), but only our hot water is softened in the kitchen.  That way we're not drinking softened water, and that's where I fill my tank.  I do mix some hot water into the cold, but the ratio is mostly cold (doesn't take much hot water to warm up to 78 degrees), so I think the sodium is negligible, and the water is going into the tanks is still at least 300 ppm GH.  Haven't had any issues in the few years I've used this system.

[tolstoy21]

This topic came up in the past. 

 My personal take is that the sodium exchange will have no effect. I run all my tank water though a nitrate filter whose resin does a sodium ion exchange and is recharged via a brine solution. I have not experienced an issue with that in the past two years.  I have crazy healthy plants and happy fish (except the dead ones!).

I did do a little little thought experiment and am convinced the sodium is negligible. Pretty sure I put as much or more more sodium in my tanks when feeding baby brine daily.

I’ll quote myself here from another thread. And while I’m not an expert on this subject, I just haven’t yet found compelling evidence that makes me believe otherwise.

On 12/24/2020 at 10:29 PM, tolstoy21 said:

A water softener will add 149mg of sodium per quart of softened water at 20 grains hardness. If your water is 8dGH then I think it’s in the area of 8 or 9 grains hardness, if my math is right. So you’re looking at 60mg of sodium per quart, approximately.

Now in comparison, seawater is 35,000mg sodium per liter of water (and a liter is pretty comparable to a quart, right?).

I apologize if my numbers are off, but if they are anywhere in the ballpark comparison wise, I’m still sticking with the sodium being negligible as added by a water softener.

Anyone dumping baby brine shrimp and their water into an aquarium to feed fish is probably far exceeding anything a softener is contributing. 

Edited April 24, 2021 by tolstoy21

[tolstoy21]

8 hours ago, lefty o said:

lets not miss the point people, all water softeners have a bypass valve on them. dont want soft water in your tank, push the bypass valve. dont want all your piping, faucets, and shower crusty, put the valve back so you get soft water. i just dont get why this is an issue, as even with a water softener in your home, if you dont want softened water in your aquarium, you dont have to.

I bypass mine as well for aquarium water, but only because I want the GH from my well, and my softener system also has resin meant to boost the Ph which is problematic for me and unpredictable in at times (in terms of my aquariums), especially after it’s been serviced by my well technicians.

[OnlyGenusCaps]

1 hour ago, tolstoy21 said:

A water softener will add 149mg of sodium per quart of softened water at 20 grains hardness. If your water is 8dGH then I think it’s in the area of 8 or 9 grains hardness, if my math is right. So you’re looking at 60mg of sodium per quart, approximately.

Now in comparison, seawater is 35,000mg sodium per liter of water (and a liter is pretty comparable to a quart, right?).

Agreed that there is a chasm of difference between what we are talking about and sea water.  I also think the point about baby brine addition is solid.

The information available about what comes through seems oddly variable depending on source.  I've gone down a bit of a rabbit hole on this.  I find the numbers that claim lower ionic concentrations coming through to be suspect, as that should not be how ionic exchange works (certainly doesn't on charged columns on scientific equipment).  Depending on the source, very hard water through a softener could bring you into the lowest range for the strictest definition of brackish water - although where people draw the line for brackish varies as well, by a factor of two!  Or I can find numbers that claim loads of calcium cleared out with essentially no sodium input.  Much like @KaitieG, I am getting a softener installed just on the hot water line.  I'm curious enough, I plant to investigate.  But for now, I must emerge from this particular rabbit hole.