Water softener toxic to plants?

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coolchinchilla

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I just received a bunch of plants from http://www.freshwateraquariumplants.com/ . I'm very pleased with them.

The instructions that came with the plants left me a little puzzled though. It said to never use warm water from the tap if you have a water softener. The plants will die if it is in the softened water. They suggest that you take only cold tap water and heat it in a bucket before putting it in the tank. --

Is this true? Is softened water that toxic to plants? When I change the water in my tanks I use warm water from the tap near the temperature of the already existing water. I'm not sure I'm ready to preheat cold water, nor do I have the equipment (20 gallon tub, aquarium heater, ph, pump).

Tanks:
15 gallon; 20 watts NO
30 gallon, 20 watts NO. (I know this is VERY low light. I hopefully have plants that will be ok under low light)

Thanks in advance.
 
Most wter softners use salt, salt = bad news for plants..

It has something to do with cation exchange, tho I can't remember if that is the good way to soften water, or the bad way.
 
Also, plants need the calcium and magnesium that the water softener removes in order to grow well.
 
It won't kill them. But it is not ideal for them either. Water softners use ion exchange (same technology used in po4 exchange resins and water softner pillows). They remove mg and ca for na. Cold tap doesn't get filtered through your softner.
 
Yep, its the fact it replaces some trace minerals like Mg and Ca, and replaces them with sodium ions.
It's not exactly the same as adding salt to your aquarium, but it does throw things outta whack, and many plant species will wilt. If the tank isn't optimal for those plants in the first place, they likely will die completely, in short order.

Most people do not run their cold water thru a softner, but a few do. Its worth checking.
 
So if I use warm water from the tap in water changes, it will be detrimental to plants??? I'm just starting a planted tank and this would be a pain for me
 
So use a newly purchased 39gallon garbage can, fill it with cold tap water, dechlor it, and toss in a 100w heater. In a few hours, you're ready to change the water.
 
Thanks every one for your input.

malkore said:
Yep, its the fact it replaces some trace minerals like Mg and Ca, and replaces them with sodium ions.

So it's better to take cold tap (which hopefully doesn't go through the water softener) hold it in a bucket, warm it to tank temp, then pump the water into the tank. 8O Hmmmmmmm... <sigh>

I guess I didn't know that plants required non-softened water to do well. I had no idea. All I read about regarding plants were things like CO2, dosing ferts, lighting, heartiness of a particular plant, when to change bulbs, what spectrum to use, number of watts per gallon, etc. Maybe I just didn't see it. No one talks about what kind of water is best for plants. If I wanted to have a low-tech, minimal work planted tank I thought I'd only have to be concerned about is lighting and dosing ferts. It wasn't mentioned under plant care on the many plant sites I looked at. Maybe it is there, but it sure wasn't as obvious as CO2 and WPG for example. Maybe someone should add this fact to one of the stickies on this forum.

I just spent $55 on plants. If I'd had known that I can't use softened water, I might have settled on plastic plants instead. Rats. Rats. Rats. I'm bummed. :cry:

Do you think I could dose in some Mg & Ca in the softened water instead? My water is liquid rock to start with (pH greater than 8.3, "hardness" is greater than 300ppm)
 
You could dose Mg and Calcium, but you'd still have all the excess Sodium from the softened water. I have no idea what issues, if any, that could pose.
 
If you choose to use warm tap, I do not think you should worry about it, since you might have enough Mg/Ca for your low light tank and plants. (They are still traces.) I do not think it is bad to use cool water for small water changes. How about mixing both taps as a comprimise, which will also lower Na concentration, and observe?

Have you considered using KCl in your water softener? I bought 40lbs for around $15 as "Sodium-Free Water Softener" from Home Depot.
 
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