# Sodium water softeners...



## Tom (19 Jan 2011)

Bad for plants? I was just wondering. In all my successful tanks I have used rain water. In all my less successful tanks I have used "softened" tap water. I know it isn't _properly_ softened as in lower GH, so is it possible that the Sodium or whatever those salt tablets are can be harmful to plants? I'm probably just trying to find a scapegoat for my recent efforts, but if anyone remembers my 40cm layouts I didn't have any issues with them. It was only when I started on tapwater that I had issues. If it is possible it's having some effect, I'm gonna start using rainwater again. 

Tom


----------



## George Farmer (19 Jan 2011)

Can't you use regular tap water?


----------



## Tom (19 Jan 2011)

We've only got the outside tap that's not softened, but I might as well use rain water if I do that. Other than that, it's the britta filter, and I'll get shot for using that!


----------



## George Farmer (19 Jan 2011)

Personally I'd use tap water from outside.  If you want it softer, dilute with rainwater.


----------



## Tom (19 Jan 2011)

I think that's what I'm going to try then, as it's worked fine before. Do you think it could be affecting anything though? It does taste nasty/salty to drink.


----------



## George Farmer (19 Jan 2011)

Well, I don't think it will be doing any good.

I'm no scientist but water softeners work by replacing calcium and magnesium with sodium ions.

Calcium and magnesium are essential macronutrients, so more is required.  Sodium is a micronutrient, so much less is necessary.

I suspect you'll see a marked improvement in plant growth when you stop using sodium-softened water.


----------



## Tom (19 Jan 2011)

Yes I think that's pretty much what it does. I was thinking more in terms of plants not appreciating salt water! Cheers. I can only try it and see if things go better. Just looking on James' planted tank site at the deficiencies. Magnesium and Calcium both say distorted leaf growth and yellowing, which I saw particularly with the R. rotundifolia. Again I hope I'm not just trying to find an excuse!!


----------



## nayr88 (20 Jan 2011)

What's wrong with water from the tap inside your house?

My tap water is hard as hell, and I've no problem growing plants or keeping shrimp and apistogrammas?

I don't think britta filters are good for tanks anyway, I can't provide evidence of this, just that's what I was told when I originally went to keep apistos and wanted softer water.

Also, I know this is england but how much rain water do you get a week? 50% water change on a 40lite means yourll need 20litres of rain water a week??? What happends in the summer? Also do you cut the water with tap water?

Cheers


----------



## Tom (20 Jan 2011)

Because all the taps in the house are "softened" with the salt tablets. The problem is not that the water is very hard, I'm guessing that it's because of high the amount of Na, and now lack of Mg and Ca. But it's still only a theory. 
I reckon there will be enough. I've got about 400 liters of water in the tank at the moment, but if I cut it 50/50 with the outside tap (not treated), then it should last a while. If not, I'll get a couple tanks of RO. It's worked before.


----------



## dw1305 (20 Jan 2011)

Hi all,


> I'm no scientist but water softeners work by replacing calcium and magnesium with sodium ions.


George is right and that is exactly what they do. It is also true that the more Ca2+ ions you have, the more Na+ ions will replace them. You could actually use potassium chloride (KCl), as K+ ions (or any other mono-valent ion) in the water softener, but I assume people don't as it is more expensive and would be unsuitable for people with kidney failure etc.. The NHS advices that you need a rising main water supply in the house that you can draw drinking water from as well, as high sodium levels in food and drink are associated with high blood pressure, increased risk of stroke etc. (although the risk associated with water softeners is very low compared with dietary factors).  If you have access to a conductivity meter? you would find that the conductivity of your softened water will now be higher than it was in your tap water. Soft, high conductivity water is unusual in natural situations (away from some volcanic or arid areas) and is quite alien to most fish and plants (even sea water has a lot of other salts in it as well as sodium) and they tend all to do poorly in it. 



> Bad for plants? I was just wondering. In all my successful tanks I have used rain water. In all my less successful tanks I have used "softened" tap water. I know it isn't properly softened as in lower GH, so is it possible that the Sodium or whatever those salt tablets are can be harmful to plants?


I don't think this is a co-incidence, excess sodium is bad for both plants and fish (unless you keep Lake Victoria Cichlids or Brackish water fish).  I have very hard water and I use rainwater, if I didn't have access to that I would use hard tap water, but keep appropriate fish (Rainbow fish, Rift lake Cichlids) and plants (_Vallisneria, Ceratophyllum_ etc.). 





> I suspect you'll see a marked improvement in plant growth when you stop using sodium-softened water.


 I would expect this as well.

cheers Darrel


----------



## Tom (20 Jan 2011)

Thanks Darrel, I really hope the water is the problem as it would give an answer so many headaches!! I know my Cherry Shrimp certainly struggled when I first got them this time round and haven't reproduced, whereas in the old tanks I had them coming out my ears (and somehow down the stairs on some occasions!) 

My Malawi's look lovely though  The baileyi puffer has never been bothered by it either. 

Thanks again


----------



## dw1305 (20 Jan 2011)

Hi all,


> Thanks Darrel, I really hope the water is the problem as it would give an answer so many headaches!


Tom, I'm pretty sure it will be the water softener. I've just looked at the price for 25kg of KCl, and it is about £35, so I'm not surprised most people use salt in their water softener. Can you use rain water? I've never had any problem with it, and even if you live in an intensive arable area (potential problems with spray drift) it should be pretty good quality in the winter. I keep_ Daphnia _in my water butts, as long as the water has swimming _Daphnia_ in it, I'm pretty confident it will be all right.

cheers Darrel


----------



## Tom (20 Jan 2011)

I've done a water change on the 10 liter with 50/50 hosepipe/rainwater and heated to room temp. I swapped out the 1/2 liter of water in my Mini M with the same too. Our house backs onto a field which does get sprayed occasionally, but the tank itself is covered so shouldn't affect much.


----------



## dw1305 (20 Jan 2011)

Hi all,


> Our house backs onto a field which does get sprayed occasionally, but the tank itself is covered so shouldn't affect much.


 I was more worried about the spray getting onto surfaces and then being washed into the water butt. I don't think herbicides or fungicides would be a problem long term (although some weed-killers are very persistent) but some of the insecticides are both persistent and damaging at very low, sub-lethal doses. 
<http://www.pan-europe.info/Resources/Briefings/Pesticides_and_the_loss_of_biodiversity.pdf> 

cheers Darrel


----------

