Using soft water in my aquaponic system

[Kim Dunn]

I am trying to finalize a design for my system to have it up and running early spring.  We have well water with plenty of iron, and we use a water softener that utilizes sodium chloride to soften the water for household use.  Assuming that we monitor and adjust the pH as needed, in what way (if any) will the   salt effect the fish and the system in general?  Any advice is appreciated.  Thanks?

[TCLynx]

It will depend on the type of softener. 

Some softeners don't actually put much if any salt into the water, they only use the salt to clean the mineral build up off the media in the softener so it is only a tiny amount of salt that gets into the water.  Other softeners don't actually remove the minerals from the water but only cause them to change into a form that won't stick to pipes or heating elements.  Yet other types seem to put much more salt into the water.

Too much sodium chloride building up in the system would not be good.

Can you do some tests of your water before it goes through the softener?  Can you use un softened water for your system?

Now some water from the softener might not be a bad thing if your softener removes the calcium carbonate from your well water and your well water has a huge amount of calcium carbonate in it in addition to the iron.

My well water is really hard and if I use it constantly to top up my system I wind up with too much calcium in the water and the pH stays too high so I try to collect rain water to balance things out and allow the pH to drop enough and let me keep the calcium low enough that the potassium remains available to the plants.  I wish I had a little more iron in my well water actually.

[Kim Dunn]

Thanks for responding, it is greatly appreciated.  We have a WaterBoss softener, which addresses only ferrous iron, manganese, hydrogen sulfide, and iron bacteria.  We tested the water at the time we installed it with test strips, so I do not have an exact number, but the pH well is above 7.  I can get it tested at a lab, though.  If I can solve this problem simply by using unsoftened water, that would work best for me.  I can run the pluming directly from the well, which is not far from the site.  Will this option be best for the plants and fish?  Is having too much iron not good for them? 

I have not ruled out using rainwater, but it is a lot of extra work for us to retrofit for it when it has not been raining consitantly, as we have a two story home.

Thanks,

Kim

TCLynx said:

It will depend on the type of softener. 

Some softeners don't actually put much if any salt into the water, they only use the salt to clean the mineral build up off the media in the softener so it is only a tiny amount of salt that gets into the water.  Other softeners don't actually remove the minerals from the water but only cause them to change into a form that won't stick to pipes or heating elements.  Yet other types seem to put much more salt into the water.

Too much sodium chloride building up in the system would not be good.

Can you do some tests of your water before it goes through the softener?  Can you use un softened water for your system?

Now some water from the softener might not be a bad thing if your softener removes the calcium carbonate from your well water and your well water has a huge amount of calcium carbonate in it in addition to the iron.

My well water is really hard and if I use it constantly to top up my system I wind up with too much calcium in the water and the pH stays too high so I try to collect rain water to balance things out and allow the pH to drop enough and let me keep the calcium low enough that the potassium remains available to the plants.  I wish I had a little more iron in my well water actually.

[TCLynx]

You can test pH and hardness using aquarium test kits, you don't necessarily need to ship it off to a lab.  But be sure to bubble the water overnight before testing the pH from the well since trapped carbon dioxide will give you a false low reading on water directly out of the pipes.

I don't know how much iron would be too much for the fish.