Acid Neutralizer or Filter Only

[Starman314]

Hi,

We had a water test performed by NTL and our well water came back with a pH of 6.4 and 20 mg/L of hardness. We are also getting a little bit of sediment build-up in our toilet tanks and faucet aerators. We have no staining on our sinks / tubs and the copper level from the water test was 0.015 mg/L.

I had three water treatment companies come out to provide recommendations:

One company recommended that we just install a big blue filter because we have CPVC pipes and the water isn't too acidic. One company suggested that we install an acid neutralizer and a big blue filter. The final company suggested that we install a softener, acid neutralizer, and big blue filter.

Which direction should we go? Do we need to increase the pH of the water if we have CPVC pipes (obviously there are still some copper fittings) or should we just focus on filtration?

 

[Reach4]

What were your corrosivity numbers?

 

[Sponsor]

 

[Starman314]

TDS - 54 mg/L
Alkalinity (CaCO3) - 34 mg/L
Calcium - 4.4 mg/L

They don't have an LI calculation, but it appears to be around -2.5 to -3 based on inputting the above values into an online calculator. Are there other numbers I should look at?

 

[Reach4]

http://www.galwaywater.ie/water-testing/langelier speaks to interpreting that number. I don't know how accurate they are, but you may want to look further. I would certainly avoid metal piping and fittings with that. CPVC was a good match for you.

I guess a 4.5x20 whole house cartridge filter might do it for you. I will mark your poll. Bigger cartridge means lower pressure drop/ longer cartridge life. I think your water is unusual enough that you may want to do more research. I am not a pro or expert and have not done that much reading about your kind of water.

 

[Bannerman]

Your plumbing lines are only part of the house plumbing system. I expect your faucets, shower heads, water heater, ice maker, dishwasher, laundry equipment etc, may contain metal components which could be negatively affected.

Suggest posting your complete test results so all water conditions may be reviewed and considered together.

 

[Starman314]

Here's the full set of test results.

 

[SuperGreg]

(I am not an expert) - I would be worried about all the other stuff that can corrode, especially inside washing machine, dish washer, etc. I have quite a bit of sediment in my well water, and almost all of it is filtered out after my neutralizer (a downflow bash flushing neutralizer will remove some sediment). You may not even need the Big Blue, but if you placed it after the neutralizer it would catch whatever was left and probably would last a while if the water was mostly clean leaving the neutralizer.

Oh one more thing - the neutralizer will harden the water. I didn't need a softener before but with the neutralizer, now I do.

 

[Reach4]

You may not even need the Big Blue,

While it is not the common thing to do, I would put a whole house cartridge filter even on city water. If you don't need it, it will still serve as a QC tool. Have you ever found stuff in your aerators on city water?

The other thing is that when calcite raises the pH, it adds hardness.

Good points on the washer etc.

 

[ditttohead]

Since you have fairly soft water a simple chemical injection pump with potash, sodium hydroxide, and maybe a little polyphosphate would be a simple fix. A Hydra pre-filter to catch anything large. If you want the Big Blue style filter may also be a good idea.

 

[Reach4]

Since you have fairly soft water a simple chemical injection pump with potash, sodium hydroxide, and maybe a little polyphosphate would be a simple fix.

That sounds really cool... a compounded prescription solution. Avoiding a softener. Nice.

Why combine potash and sodium hydroxide? I figured they were roughly equivalent.

 

[Starman314]

How much maintenance is the injection system relative to a backwashing calcite filter? Given that our current water is relatively soft, what are the odds that we will need a softener if we use a calcite filter? I'd like to try to correct the issue with the lowest amount of ongoing maintenance + cost.

 

[ditttohead]

I may have described it wrong. You can use either but Sodium Hydroxide is a lot stronger and needs to be treated with great care. Potash is fairly safe by comparison.

The injection system has a simple learning curve. Set it up once, test it and adjust it a few times, then you basically just add the potash or whatever chemical you want to use to the tank with the proper amount of water, mix it up and your done. Most pumps used for this require the pump tube be replaced annually but this is about a 1 minute job.

Calcite will likely add enough hardness to be annoying. You don't have to have a softener, totally up to you. You do need to correct your pH.