RODI Help - TDS

[alyxandria]

Hey all! I got a new (to me) 4-stage RODI system. The lady said that the cartridges were recently replaced and should last me a year. I have a ZeroWater filter for our drinking water and it read 0ppm when I tested it to make sure the meter was working. My tap water is 146ppm. I ran the RODI in a bucket and it came to 49ppm but then I realized the bucket was one I used to mix saltwater in before and I didn't rinse it out entirely so I assume that was why. I'm going to buy a fresh bucket. I grabbed a clean glass and tested some water and it was 14ppm. I'm assuming 14ppm is what my RODI is producing and I'm not sure why.

Shouldn't this be 0ppm? Do I have it set up wrong? Should I replace a cartridge (and which one?)





The yellow tube is attached to the sink which runs through the front of the sediment filter, then from the back of the sediment it runs to the back of the carbon. From the front of the carbon it runs up to the RO and from there a red tube runs to waste and a blue tube runs into the back of the DI and out the front and into my bucket. This all sounds correct right?

[mr_X]

It sounds right. Did you replace the DI resin? How many gallons have you run through it since? You may have to run it a little to break the new filters in and let the loose carbon escape.

[alyxandria]

I haven't replaced anything. I've only run about 5 gallons so far. Not sure how many the previous owner ran through.

Do you think running it overnight with both returns in the sink would help it out?

I was told by someone to let it run for half an hour then test it and start bucketing the RODI water because it takes a while to get to the lowest TDS.

[mr_X]

In the beginning, right after a filter change you might see raised tds, but it shouldn't take too long. Overnight is longer than you need to waste water. I think the DI resin needs changing. Bulk Reef Supply is pretty cheap for that sort of thing in case you were wondering.

[Adamski]

I discard the first 10 minutes worth of water. I have a flush valve which helps


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[old man]

Would Prime work?


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[alyxandria]

Originally Posted by old man

Would Prime work?


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.. What for?

[alyxandria]

Should I go with....

http://www.aquacave.com/spectra-pure...b-ci-10hc.html

Or this?

http://www.aquacave.com/di-resin-mix...ging-1137.html

Only thing I'm not sure of is if the cartridge I have now is a refillable one or if I need to buy one.

I let it run for 15 minutes or so and it came back at 20ppm. I am going to try it again tomorrow after class. I'll let it run for 30 and test with my TDS meter.

[mr_X]

You need a refillable DI cartridge. I like shopping at BRS-
BRS Bulk Deionization Resin - Color Changing - Bulk Reef Supply
See if it unscrews and you can dump the stuff out. Otherwise you'll need to purchase-
Clear Refillable Cartridge for DI Resin - Bulk Reef Supply

[alyxandria]

Originally Posted by mr_X

You need a refillable DI cartridge. I like shopping at BRS-
BRS Bulk Deionization Resin - Color Changing - Bulk Reef Supply
See if it unscrews and you can dump the stuff out. Otherwise you'll need to purchase-
Clear Refillable Cartridge for DI Resin - Bulk Reef Supply

Awesome thank you!!

[alyxandria]

I have a question - the water goes into the DI cartridge from the outside and from the middle of the cartridge up. However, it's not really filling up. Is this an issue?

I'm ordering that resin and the refillable part tonight.

I thought I'd run it for an hour or two to see if it makes a difference.

Could the RO filter be positioned wrongly? I can't get it open - have to wait until my boyfriend gets home to see if he can open it and see if it's in right. The manual said that could be why I would be getting poor water quality.

[mr_X]

If the R.O. membrane is not functioning properly the DI resin would get spent as a super fast rate, but I believe if the TDS is 20, the RO is working. If it wasn't functioning at all the I believe the TDS would be much higher.

[alyxandria]

Originally Posted by mr_X

If the R.O. membrane is not functioning properly the DI resin would get spent as a super fast rate, but I believe if the TDS is 20, the RO is working. If it wasn't functioning at all the I believe the TDS would be much higher.

Good point.

I checked the water (running since my last post - 3hrs ago) in a clean glass and it's now reading 10ppm as opposed to 20ppm.

I also flushed it for 15 minutes before I started running it. Then I ran it properly through.

If I keep running it do you think it might continue to go down? I'm on a well and it's running cool (not cold) water so it's not emptying my hot water tank so I can keep it running.

I was told the filters were "replaced recently and should last me a year" from the previous owner who is big into the saltwater hobby (had a private distribution business) so I'm wondering if the filters just need to be run through?

Regardless, I'm ordering new cartridges so Ill have them if all else fails.

[mr_X]

I can't speak for the seller, but I will tell you that every time I would see a T5 or metal halide fixture for sale on forums they ALL had brand new, or slightly used lamps- not once have I seen someone selling a fixture and them telling buyers the first thing they have to do is replace expensive lamps, so, from that I always assume the worst.

As for the TDS continuing to come down, if the total time running it was an hour or two, then I think it's as good as it's gonna get.