tds readings

"erik" wrote in message
...
Your argument makes sense. My source of info has not always been as
right as he would like me to believe.

Has anyone else had experience with this? I did a lot of research at
the time and didn't find much on the web discussing non-chlorinated
water and CTA membranes.

Anyway, my TDS readings still look ok. Not great but I though they
were OK for CTA.
My new TDS meter is on loan to a friend but the readings I got a
couple of weeks ago were roughly :
tap = 850
RO = 80


Humm....
From tap = 850? I have not seen this high reading before or know anyone
else. Do you know anyone have TDS meter or can you double check this reading
with your LFS [if possible]? Could this be a bad TDS meter? It just a guess
here.

CapFusion,....

Sorry, my mistake. Too many percosets that night )
That would be 850 uS and 80 uS respectively.
I know that's still pretty high so maybe the meter does need
calibration. It's a Hanna Instruments 98311 EC/TDS & Temperature
Meter. It's new, right out of the box and probably does need
calibration. But regardless of the actual values, 80 is roughly 10%
of 850 which was the point I was trying to make.

Sorry for the confusion,
Erik

On Mon, 9 Aug 2004 13:16:49 -0700, "CapFusion"
CapeFussion...@hotmail.., com wrote:


"erik" wrote in message
.. .
Your argument makes sense. My source of info has not always been as
right as he would like me to believe.

Has anyone else had experience with this? I did a lot of research at
the time and didn't find much on the web discussing non-chlorinated
water and CTA membranes.

Anyway, my TDS readings still look ok. Not great but I though they
were OK for CTA.
My new TDS meter is on loan to a friend but the readings I got a
couple of weeks ago were roughly :
tap = 850
RO = 80


Humm....
From tap = 850? I have not seen this high reading before or know anyone
else. Do you know anyone have TDS meter or can you double check this reading
with your LFS [if possible]? Could this be a bad TDS meter? It just a guess
here.

CapFusion,....

"That would be 850 uS and 80 uS respectively."

And roughly divide by 2 for TDS

850 = 425 TDS

80 = 40 TDS

You have some hard water but I have seen higher. EPA drinking std are not to exceed 500
TDS (IIRC)
--
Boomer

Want to talk chemistry ? The Reef Chemistry Forum
http://www.reefcentral.com/vbulletin/index.php

Want to See More ?
Please Join Our Growing Membership
www.coralrealm.com

If You See Me Running You Better Catch-Up
"erik" wrote in message
...
: Sorry, my mistake. Too many percosets that night )
: That would be 850 uS and 80 uS respectively.
: I know that's still pretty high so maybe the meter does need
: calibration. It's a Hanna Instruments 98311 EC/TDS & Temperature
: Meter. It's new, right out of the box and probably does need
: calibration. But regardless of the actual values, 80 is roughly 10%
: of 850 which was the point I was trying to make.
:
: Sorry for the confusion,
: Erik
:
: On Mon, 9 Aug 2004 13:16:49 -0700, "CapFusion"
: CapeFussion...@hotmail.., com wrote:
:
:
: "erik" wrote in message
: .. .
: Your argument makes sense. My source of info has not always been as
: right as he would like me to believe.
:
: Has anyone else had experience with this? I did a lot of research at
: the time and didn't find much on the web discussing non-chlorinated
: water and CTA membranes.
:
: Anyway, my TDS readings still look ok. Not great but I though they
: were OK for CTA.
: My new TDS meter is on loan to a friend but the readings I got a
: couple of weeks ago were roughly :
: tap = 850
: RO = 80
:
:
: Humm....
: From tap = 850? I have not seen this high reading before or know anyone
: else. Do you know anyone have TDS meter or can you double check this reading
: with your LFS [if possible]? Could this be a bad TDS meter? It just a guess
: here.
:
: CapFusion,....
:
:

"Boomer" wrote in message
...
"That would be 850 uS and 80 uS respectively."

And roughly divide by 2 for TDS

850 = 425 TDS

80 = 40 TDS

You have some hard water but I have seen higher. EPA drinking std are not
to exceed 500
TDS (IIRC)

Thank Boomer.

Erik,
Ahh... that more about right. But as for the product from RO should not be
that high with 100GPD. IIRC from previous post, you have DI unit too. From
that DI output should be close to non-detectable. From your RO output, that
seem to be still high. 40TDS is similar to SF water without using any RO
unit.

You might want to check what the PSI before going into the unit. Do your RO
have a PSI meter? If so, what it indicating?

CapFusion,...

No DI yet. I'm looking into building one. PVC pipe is cheap )

Anyway, 40 ppm TDS may still be high but if I'm getting a 90 to 95 %
reduction in TDS after the RO should I be expecting better of a CTA
membrane?


Erik

On Fri, 13 Aug 2004 13:12:11 -0700, "CapFusion"
CapeFussion...@hotmail.., com wrote:


"Boomer" wrote in message
...
"That would be 850 uS and 80 uS respectively."

And roughly divide by 2 for TDS

850 = 425 TDS

80 = 40 TDS

You have some hard water but I have seen higher. EPA drinking std are not
to exceed 500
TDS (IIRC)

Thank Boomer.

Erik,
Ahh... that more about right. But as for the product from RO should not be
that high with 100GPD. IIRC from previous post, you have DI unit too. From
that DI output should be close to non-detectable. From your RO output, that
seem to be still high. 40TDS is similar to SF water without using any RO
unit.

You might want to check what the PSI before going into the unit. Do your RO
have a PSI meter? If so, what it indicating?

CapFusion,...

"erik" wrote in message
...
No DI yet. I'm looking into building one. PVC pipe is cheap )

Anyway, 40 ppm TDS may still be high but if I'm getting a 90 to 95 %
reduction in TDS after the RO should I be expecting better of a CTA
membrane?



When I see 40ppm reading from TDS and want to consider this to be a puriest
source water mix for a reef tank, I would hestitate a bit. But for human
consumption, than, I would say ok. 40ppm reading, will cause algae war /
battle to eternity and normally algae will have the advantage over you. I do
not know much regarding CTA type membrase in RO but as general RO concern,
it should bring down to something like 10ppm or so with TFC or similar
membrane.

With 40ppm, I would suggest using DI unit to further reduce this
filteration. Or change your membrane beside CTA and see if you have better
result without DI unit.

CapFusion,...