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View Full Version : tds out put went up after long use?


shikhyung
01/20/2009, 08:16 AM
Hi, I notice when first turn on, the TDS meter reading (after membrane) is 008, and stay low for half of the day, then climb up to 125 after another 1/2 day. Is this normal?
(What I do is collect 50gallons every 3 weeks, then shut the valve off).
Thanks.

Buckeye Hydro
01/20/2009, 05:19 PM
You should change your proceedure so that you use the sytem at least once per week.

What you describe with the tds of your RO water climbing is not normal and indicates something is wrong.

We'll need more information to troubleshoot the system. Would you like to answer some questions?

Russ

shikhyung
01/20/2009, 10:41 PM
What question, obviously, I would like to solve the problem.
One more thing, the next time when I collect water it will happend the same as said above.
I have a 5 stages with tank reserve for drinking. Therefore, drinking water is collect every day. When collect water for the aquarium I turn off the valve to the 3 gallons drinking reserve tank. the line to the DI cartridge has a check valve itself. Thanks.

Buckeye Hydro
01/21/2009, 03:29 AM
Here's a few to get started:

What is your water pressure at the membrane?

How are you measuring the TDS in the RO water? What sort of meter, container, how do you access your RO water, etc...

Russ

shikhyung
01/21/2009, 08:18 AM
What is your water pressure at the membrane? Unknown

How are you measuring the TDS in the RO water? What sort of meter, container, how do you access your RO water, etc...
DM1 dual tds. mount across DI cartridge. It's a 5 stages system 75gpd, at the output, I split in 2: one go to check valve then go to DI then store in a 50 gallons food grade tank, the other go to( a valve placed here , close when collect DI) the RO 3 gallons reserve tank.

Buckeye Hydro
01/21/2009, 05:48 PM
What is the tds of your 1) tap water, 2) RO water, and 3) DI water?

I'm not clear on where you have the DM1 probes installed. Maybe you can send some pictures?

shikhyung
01/21/2009, 09:40 PM
What is the tds of your 1) tap water, 2) RO water, and 3) DI water?
1)~400, 2)consider 8, I guesss, 3) 000 , change resin when 001.

I'm not clear on where you have the DM1 probes installed. Maybe you can send some pictures?
The DI is the adding station, therefore the 2 probes are mounted at IN and OUT post of the cartridge.

Buckeye Hydro
01/22/2009, 03:39 AM
OK. It sounds like that with the tds readings you report here: 400, 8, 0 - your system is working fine. I suspect that the odd reading you got was an anomaly....

Russ

shikhyung
01/22/2009, 07:06 AM
Do you think collect water all day long like I did will exhaust the membrane?

Buckeye Hydro
01/22/2009, 04:08 PM
No sir. These sytems work better when they are run for longer periods versious being run with frequent on/off cycles.

shikhyung
01/22/2009, 09:22 PM
Then what is wrong with my system? I meant what causes it jump after more than 1/2 day running

Buckeye Hydro
01/23/2009, 04:21 AM
I suspect nothing is wrong with it.

What you experienced was probably an artifact of a erroneous reading on your meter - bad batteries? misaligned probe? scale broken loose and lodged on the probe? biofilm related material on the probe, etc., or an artifact of the way the tds was read (e.g., tds creep water).

Your readings now (400, 8, 0) indicate the system is working as it should. In fact, your membrane is showing a 98% rejection - that is very good.

Would be a good idea to get a pressure gauge on the system so you know when/if your prefilters are clogging.


Russ

shikhyung
01/23/2009, 10:08 PM
Well, ....I guess I have to figure it myself. Thanks.