Well water and RO/DI

[Dan1789]

I hooked my Rodi unit up to my well, with a booster. I installed new micron, gac, and DI resin filters. After only 20 gallons made, my micron filter is a rust orange color and its reading 130 TDS in the new water. Any ideas what's going on?

 

[uall8up]

Very nasty water!!!

 

[kschweer]

Very nasty water!!!

+1. Lol. How does your DI cartridge look? I wouldn't be too worried about the first stage being discolored its doing its job and filtering out the "bigger" stuff in the water. I would guess that your well water is high in carbon dioxide which will deplete your DI cartridge very quickly. What is the TDS coming into the unit?

 

[kschweer]

Also I would use a sediment filter in the first stage as opposed to the micron and a carbon block instead of the gac.

 

[Mrfresh]

Well the nice thing with a well is it will have a lost of minerals but at the same time has a lot of sediment in it.
I would look into getting the 2 strange pre filter before it goes into ur rodi unit, to try and help get out everything.

 

[Dan1789]

TDS is reading 130 in the water I just made. I'm thinking I might be better off just hooking it back up to the city water.

 

[Dan1789]

DI resin looks fine, but it's brand new still. I tried it once before without the booster pump and the pressure was terrible, barely made water and destroyed the DI resin.

 

[Dan1789]

Oh sorry, misread your question. I will check the TDS of the well water in the morning.

 

[Reef Pets]

Well water will absolutely destroy DI resin. There is a filter media made for well water, buckeye field supply has them. Also, I would highly recommend an arsenic filter as well and probably an iron filter... The only way to know what needs filtered out is to have the water analyzed.

 

[AZDesertRat]

Sampling directly from the sources, what is your well water TDS, RO only TDS before the DI and final RO/DI TDS directly from the filter, not a bucket or ATO storage?

What RO membrane do you have and how old is it? What is your exact measured waste ratio using a measuring cup and clock or watch timed for one minute from both the treated and waste lines.
What is your water pressure and water temperature?

What micron rating is the sediment filter and I hope you really didin't install a GAC filter rather than the carbon block you should be using.

Well water is no harder on filters or DI is it is handled properly. CO2 may be an issue on the DI life but we need to pool at other issues first.

 

[pickupman66]

Sampling directly from the sources, what is your well water TDS, RO only TDS before the DI and final RO/DI TDS directly from the filter, not a bucket or ATO storage?

What RO membrane do you have and how old is it? What is your exact measured waste ratio using a measuring cup and clock or watch timed for one minute from both the treated and waste lines.
What is your water pressure and water temperature?

What micron rating is the sediment filter and I hope you really didin't install a GAC filter rather than the carbon block you should be using.

Well water is no harder on filters or DI is it is handled properly. CO2 may be an issue on the DI life but we need to pool at other issues first.

This ^ getting readings from several stages in the process is what we need. to me, with what you said, your membrane is not working at all. neither is your DI.

 

[jservedio]

If it is turning rust colored, you probably have a really high iron content in your water. This is a notorious problem with well water. You will probably have to buy an iron pre-filter for your RO/DI unit. You can buy an iron test to check the level in PPM or send out a sample - but you have the telltale rust color on your filters.

 

[cdness]

I have the iron issue as well as high CO2... over 600 TDS before the first sediment filter so it is pretty horrible.

I tested my water at many stages and decided in order to preserve the expensive cartriges I am making some changes... Below is the flow of the water and how it will be set up moving forward:

1. Backflushable sediment filter (10 micron I believe)
2. Booster Pump w/pressure regulator
3. Sediment filter (1 micron Spectrapure)
4. Sediment filter (.5 micron Spectrapure)
5. Carbon block (.5 micron Spectrapure)
6. RO Membrane (90 GPD Spectrapure)
7. CO2 Degassing Tower (DIY)
8. DI Cartridge (Regenerated)
9. DI Cartridge (Regenerated)

Some things I have found:

* The different DI resins do not matter if you have high CO2 in your water. The Spectrapure MaxCap and SilicaBuster ones last a little longer than the standard mixed bed, but not enough longer to justify the replacement with them for me.

* The different carbon blocks don't seem to do anything different, so use what works for you.

* I will be testing the degassing system soon and will have a build thread up when tested. I need to make sure it works and doesn't flood my home...

So test your water at the stages asked for by AZ. It will help determine if the RO membrane is doing its job. That is the first to verify as you will kill your DI quickly if the RO isn't up to par.

 

[blufin]

I had the same issues with my well water. It's wasn't quite as bad as yours, but my resin filter would be toast after about 30-40 gallons. I had to resort to using a local water/pool supply place that charges $.25 per gallon for absolutely perfect water. 0 TDS all the time. It's just a hassle to lug the water around, but much cheaper than buying filters. Good luck.

 

[AZDesertRat]

Rust coloration is not always a huge problem as long as it is not plugging the sediment filter causing a pressure drop. Before my utility changed from deep wells to treated surface wate rI had rust coloration on my sediment filter also but it did not seriously affect pressure in the normal 6 month filter replacement cycle. If the pressure drop is enough to starve the booster pump then you may need a different prefilter setup but there are options such as backwashable ceramic filters or pleated filters which can be rinsed and reused.