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vader88
07/24/2011, 05:34 PM
I currently have a 5 stage unit and seem to be depleting resin fast. Here's my configuration


Incoming TDS - Unknown
TDS out of RO - 3
TDS out of DI - 3
incoming pressure 65psi

FilmTec 75gpd
I plan on picking up another meter to put inline to check input water. I'm on a well.

I recently replaced my resin since my last batch went really quick ( 2 weeks ). I was advised I may not have packed the beads to tight or may have just been some user error. I know you can't rely on color changing, but if it's any indication, I will deplete the resin again in about 12 days. Been in for 4 days and is 1/3 brown.

Some are saying it's possibly high CO2 content that's burning though it. Is there any cost effective way to correct this ? I really hate to spend 30 bucks a month on resin.

All filters are new on the unit including the membrane. What test do I need to perform to give some better ideas ?

Thanks

Tim

Buckeye Hydro
07/24/2011, 06:18 PM
With the TDS of your RO water at 3 ppm, you should get about 1700 gallons to a single DI cartridge.

Would you measure the alkalinity and pH of your Tap water and your RO water?

CO2 in the water isn't hard to remove. Let's see if that's your issue.

Russ



I currently have a 5 stage unit and seem to be depleting resin fast. Here's my configuration


Incoming TDS - Unknown
TDS out of RO - 3
TDS out of DI - 3
incoming pressure 65psi

FilmTec 75gpd
I plan on picking up another meter to put inline to check input water. I'm on a well.

I recently replaced my resin since my last batch went really quick ( 2 weeks ). I was advised I may not have packed the beads to tight or may have just been some user error. I know you can't rely on color changing, but if it's any indication, I will deplete the resin again in about 12 days. Been in for 4 days and is 1/3 brown.

Some are saying it's possibly high CO2 content that's burning though it. Is there any cost effective way to correct this ? I really hate to spend 30 bucks a month on resin.

All filters are new on the unit including the membrane. What test do I need to perform to give some better ideas ?

Thanks

Tim

vader88
07/24/2011, 06:26 PM
Thanks Russ,

Can I just purchase a standard reef test kit to get those measurements ? Or do I need something more specific ?

Thanks

edit -

according to the pH probe in my tank, it is 6.96 . I don't know how accurate that is since the the probes are calibrated for more of the high range, but I suspect it is real close.

Buckeye Hydro
07/24/2011, 07:27 PM
In your tank?

The measurements need to be taken of your tap water and your RO water.

Just make sure whatever test kit you get can take these measurements.

Russ

vader88
07/24/2011, 08:11 PM
In your tank?

The measurements need to be taken of your tap water and your RO water.

Just make sure whatever test kit you get can take these measurements.

Russ

Oops, guess I should have clarified. I took the probe from my tank and put it in a glass of the tap water.

6.96 at the tap
6.50 after RO
8.6 after RODI

I see if I can find a kit locally tomorrow for the alkalinity.

vader88
07/25/2011, 10:23 AM
The only test kit I found was carbonate hardness which I believe is more or less the same thing. Coming out of the tap it is 4dkh

vader88
07/25/2011, 11:36 AM
The only test kit I found was carbonate hardness which I believe is more or less the same thing. Coming out of the tap it is 4dkh

Just reread your question, going to test the RO water now

2 dkh after RO membrane, so to recap

6.96 after tap 6.50 after RO pH
4dkh after tap 2dkh after RO alk

vader88
07/25/2011, 12:57 PM
just as a test, I took the RO water and aerated it for about 5 minutes and the pH went to 8.05

Buckeye Hydro
07/25/2011, 06:07 PM
About 19 ppm co2 in your RO water.

So about 86% of the DI resin use is due to the CO2.

And as you saw - a little aeration made a big difference! So you'll want to run your RO water into a container which you aerate. You'll have to do some experimented re how long to aerate it - this will be affected by how much air you run through the RO water, and CO2 level in the air you pump into the water. You could use some BFS-442 CO2 Arrestor Media if you want to make sure you're not pumping any co2 into the reservoir if you are having trouble getting fresh air to your aerator intake.

Russ

vader88
07/25/2011, 06:46 PM
If I built one of those degasser's would I be able to do this..


RO >>> Degasser >>>> DI

or do I need to have some sort of dwell time ?

I've browsed and I'd like to see it visually but haven't been able to find much.

Buckeye Hydro
07/26/2011, 02:27 AM
Right - RO -> aerated reservoir with some dwell time ->DI

I don't know how much water you need to make how quickly, but size your reservoir accordingly. Best if the reservoir is tall and narrow so that you can maximize exposure to the air bubbles.

vader88
07/26/2011, 07:34 AM
Thanks Russ

Everthing clicked this morning how to set it up while I was driving around. Will cost under a hundred bucks to do it. Should be making a order with you this week. Couple questions

Would a aqualifter pump provide enough aeration with a bubble wand in a 33 gallon brute ?

Can you aerate too long ? and what is the minimum ?

Buckeye Hydro
07/26/2011, 05:36 PM
Sorry but I have never used an aqualifter pump - can't advise you there.

No danger of aerating too long. You'll have to see what works in your situation, but I'd try to start with 15 minutes and see how that works.

Russ

vader88
07/26/2011, 06:32 PM
any particular pump and airstone you would suggest using. I'm noticing my ph isn't rising like it did before in a larger container. Don't know if it matters but I'm just playing with straight tap water, not RO.

Buckeye Hydro
07/26/2011, 07:20 PM
Not relly. I know a Medo linear piston pump works well for counter surrent skimmers - you can ususally find them on ebay at a reasonable price. I remove the covering on a 10" x 2.5" carbon block, and use it as an extra large airstone hooked to my Medo.

Russ

vader88
07/27/2011, 11:55 AM
Most of the medo's are used, on found something similar, do you think this would cut it or need something more powerful

http://www.aquacave.com/eco-plus-3-commercial-brair-pump-35w--65lmin-1345.html

Buckeye Hydro
07/27/2011, 12:12 PM
I wish we could better advise you on the air pumps but we've never carried tham and no one here has significant experience with them. Sorry.

Russ