Strange Water Parameters Question (sponsored by my water softener)

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redfraggle

Aquarium Advice Apprentice
Joined
Jun 3, 2011
Messages
11
Location
NC
I have very strange water parameters out of the tap, thanks to my water softener (which uses salt):
GH=0
KH=300ppm + (off the chart, really)
pH=7.8

Do I need to tamper with these levels before I add water to the tank, or should I just add the water as is? Currently I add Prime and Flourish during weekly PWCs, and just started Excel daily.

I know products like Seachem Neutral Regulator and Tetra Correct pH 7.0 bind ammonia and starve plants. Products like API pHdown have no phosphates and are supposedly plant-safe, but would they work with such a high KH? I want levels to be acceptable for fish and plants, but I am afraid of creating a pH yo-yo effect and killing everything. I also want to make sure my plants are getting what they need; GH=0 means no Ca or Mg in the water, right? Is that okay?

I have a planted 20 gallon long with 5 neon tetras, one guppy, 4 ghost shrimp. My plants are ludwigia repens, java ferns, and crypts in FloraMax substrate. (I plan to add more plants when my 65W CF fixture comes next week).

These readings are consistent as measured by Tetra Easy Strips (and whatever my LPS uses).

The softener softens the whole house and the bypass valve is under the house (crawlspace, not basement), so a non-softened water source is not an option without special equipment or bottled water (too expensive).

I would appreciate any suggestions! Thanks!
 
The test stripes are notorious for being inaccurate. The KH should not be off the chart if the pH is 7.8 .... You might not want to base your water doctoring on those results.

I suspect that your water is rather hard to start with, with high GH & KH. An ion exchange softener exchanges the Ca & Mg for either Na or K, so it drops your GH to zero. However, the water is still hard as far as the fish is concerned. The osmotic load is actually increased as you need to exchange 2 Na of K for one Ca or Mg.

Ideally, you want to use water before the softener, as that is actually less hard & prob better for the fish. However, hardy fish prob can acclimatize to the higher osmotic load, and in your case it is prob not worth the trouble to crawl under the house to attach a hose for the bypass. Also, I would not attempt to alter the pH. It is not that high & adding chemicals will likely cause yo-yoing & do more harm than good. <If you need to control the pH, the best ways is to go Reverse osmosis & adding a proper buffering salt.>

Is the softener a K or a Na exchange? Assuming that your GH is ~ the same as the KH, you would have 500 or 600 ppm of Na or K in the water. There is no problem with high K (plants thrives on it!), but high Na tends to kill plants. <Sensitive plants die at 0.05%, and most can't stand 0.1% ... and 0.05% is 500 ppm.>

The lack of Ca & Mg will not be good for inverts (shell is Ca, without it they can't make shell, so won't do well) nor plants. You will need to add a Ca & Mg source for the plants & shrimp. If you are following the EI regime, the fert schedule has GH booster included, and that would be a reasonable source of nutrients for the plants.

EI light: for those less techy folks - Aquarium Plants

if you are using a Na exchanger, you might find your plants don't grow well due to the Na salt. In that case, you may have to consider using a R/O unit, or mixing your water with some bottled distilled water, etc. But to get a good idea of what you need to do, you need some accurate readings for the softened water.
 
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The test stripes are notorious for being inaccurate. The KH should not be off the chart if the pH is 7.8 .... You might not want to base your water doctoring on those results.

I suspect that your water is rather hard to start with, with high GH & KH. An ion exchange softener exchanges the Ca & Mg for either Na or K, so it drops your GH to zero. However, the water is still hard as far as the fish is concerned. The osmotic load is actually increased as you need to exchange 2 Na of K for one Ca or Mg.

Ideally, you want to use water before the softener, as that is actually less hard & prob better for the fish. However, hardy fish prob can acclimatize to the higher osmotic load, and in your case it is prob not worth the trouble to crawl under the house to attach a hose for the bypass. Also, I would not attempt to alter the pH. It is not that high & adding chemicals will likely cause yo-yoing & do more harm than good. <If you need to control the pH, the best ways is to go Reverse osmosis & adding a proper buffering salt.>

Is the softener a K or a Na exchange? Assuming that your GH is ~ the same as the KH, you would have 500 or 600 ppm of Na or K in the water. There is no problem with high K (plants thrives on it!), but high Na tends to kill plants. <Sensitive plants die at 0.05%, and most can't stand 0.1% ... and 0.05% is 500 ppm.>

The lack of Ca & Mg will not be good for inverts (shell is Ca, without it they can't make shell, so won't do well) nor plants. You will need to add a Ca & Mg source for the plants & shrimp. If you are following the EI regime, the fert schedule has GH booster included, and that would be a reasonable source of nutrients for the plants.

EI light: for those less techy folks - Aquarium Plants

if you are using a Na exchanger, you might find your plants don't grow well due to the Na salt. In that case, you may have to consider using a R/O unit, or mixing your water with some bottled distilled water, etc. But to get a good idea of what you need to do, you need some accurate readings for the softened water.

Wow. I just wanted to jump in here and say that was a fantastic response. For people in this situation...what do you recommend being the type of additives used to introduce Ca & Mg to the water?

I actually run a water purification company, and your knowledge of how it relates to aquariums is far and above my range. Thanks for the info :)
 
jsoong - Thanks so much for that excellent reply!

What should I use instead of those test strips to get an accurate reading on my water?

I am using sodium for my softener atm, but I think I will be switching to potassium. Potassium has other benefits, and the aquarium may be the straw that broke the camel's back.

I have not been following the EI regime, but it looks like a good idea (and my new light got here a week early :)). Would I want a GH booster if my GH is high to begin with, though?

Thanks again!
 
If your water is super hard to start with (say GH in 300 ppm range), then a Na exchanger is really not that good for your health. Since you are going to have double that Na after softening, and you will be drinking 600 ppm Na in your water. The EPA suggest 20 meq/l of Na for drinking water for those on sodium restricted diet, so 600 is way over the limit for people with heart disease, hypertension, etc. And I don't think it is that healthy for healthy people either. So switching to a K exchanger is a good idea for both you & your fishies.

Of course, we can't be sure what the original GH is. <Since I am not going to trust your KH test stripe as it does not jive with the pH number.> Your simplest way to find out the water composition is to look it up with your water co. Mine post all the results on line, so I can read the Ca, Mg, CO3 & other values. This is going to be more accurate than any hobbyist kit you can buy. For the hobbyist test kit, a liquid kit is by far more reliable than the stripes. The API kit has a good reputation & is quite reasonable. Some (esp. the salt water people) thinks that more expensive kits like Red Sea are better. But I think API will give a good enough ball park figure for us to work with if you can't get the numbers from your water co.

<You can also send away your water for professional testing. This is recommended if you are going to be tinkering with your drinking water .... In Canada, the public health units will do free well & other non-municipal drinking water testing for free.>

Since your water softener removed the Ca & Mg, you actually don't have high GH water anymore, so you would need to add that for your plants & shrimps. Barr's GH booster is CaSO4, K2SO4 & MgSO4. You don't have to use a prepared mix at all. You can use your own source of Ca & Mg.

MgSO4 (epsom salt) is cheap & easy to find so that is the standard Mg supplement for most people. For Ca, the easiest to find is CaCO3 (crushed coral, shells, etc.) This will increase your pH, and I don't know how well it will dissolve into water at 300 KH (as that is approaching the saturation point for carbonates). To add Ca without altering the KH & pH, you can use CaCl2 or CaSO4.

I use KNO3 for my K source ... adds both K & nitrogen at the same time ... but if you use a K exchanger, you don't have to add any K at all.
 
So I dug up my notes about our water quality from when we had our softener installed earlier this year. Our water hardness was only 10 grains per gallon, which is 171 mg/L (ppm). According to the Morton Salt Water Softening FAQ, this means we have 79 mg/L of sodium added to the water from our softener. This is significantly under the 0.05% aka 500ppm danger level mentioned above. The GH buffer in the EI regime should take care of the Ca and Mg for the plants and shrimp. Although I still plan on switching to potassium in the softener, I think I can safely continue to use my tap water until then (still quite a bit of salt in the bin). Does this seem sound?

Again, thanks so much for helping me sort this out.
 
Yep, 170 ppm of hardness is much more reasonable for a pH of 7.8. That is perfectly fine for fish & plants, so your plan sounds reasonable.

I must admit I did a bit of bad math in my original Na level estimate! <Trying to do it in my head by memory is not a good thing! :)>

New figure: If Ca is 300 ppm, that is ~8 meq/l, after softening, Na = 16 meq/l or ~350 ppm (not 500 or 600 as stated.) I figure your softened water should have ~175 to 200 ppm Na with the new GH figure. A bit higher than your source, but not too bad in any event.
 
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