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salty joe
04/20/2015, 08:41 AM
Is there any real advantage to using a 0.5 micron carbon block versus a 1 micron carbon block if it is preceded by a 0.5 micron sediment filter?
slief
04/20/2015, 08:47 AM
Sure. The lower the micron, the longer the next cartridge down steam will last.
salty joe
04/20/2015, 01:01 PM
Agreed, but if the sediment filter is already 0.5 micron and in front of the carbon block, the carbon block shouldn't see anything larger than 0.5 micron.

So my thinking is, a 1 micron carbon block with a 0.5 micron sediment filter in front of it would adsorb as well as a 0.5 micron carbon block with a 0.5 micron sediment filter in front of it.
aclinville
04/28/2015, 08:58 AM
It's still better because some things will get through
Buckeye Hydro
05/25/2015, 06:02 AM
Often the smaller the pore size on a carbon block the greater the chlorine capacity of the block. When in doubt, read the fine print...
salty joe
05/25/2015, 06:38 AM
Often the smaller the pore size on a carbon block the greater the chlorine capacity of the block. When in doubt, read the fine print...

Ohhhhh, thanks!
Rusland07
05/25/2015, 09:40 AM
Why is my DI Resin i bought from eBay being used up so quickly?! My TDS IN is only 5, yet - its fully used up within 40 gallons. My pressure great (50-60), I avoid TDS Creep and always let it drain in the waste line for 15 minutes to make sure the TDS IN level is brought down to the lowest. Then I insert the resin canister afterward.
Buckeye Hydro
05/25/2015, 09:45 AM
1. DI Resin from EBAY
2. exhausting quickly.

I wonder if No. 1 and No. 2 are related.
edog45
05/25/2015, 03:37 PM
DI resins are not all the same quality. Also are you packing the resin in when replacing or just filling up the canister? If it's not packed it will not last long.
Buckeye Hydro
05/25/2015, 03:44 PM
When mixed bed resins are not packed tightly, its not that they exhaoust quickly, its just that the mixed bed fluidizes and then the anion and cation beads separate by specific gravity - and you no longer have a mixed bed.

Russ
salty joe
05/25/2015, 07:16 PM
I've read that two mixed beds are better than the same resin with cation resin and anion resin in separate canisters.

If that's true, any idea how much better?
Buckeye Hydro
05/26/2015, 03:49 AM
That is true. If you were getting 0 ppm out of the mixed bed and then the bed separates, we often hear of people getting 3 or 5 ppm.
salty joe
05/26/2015, 04:29 AM
Would you expect that from separate beds? I can't imagine why two mixed beds would perform better that two separate beds of the same resin.

I'm talking about separate canisters for each resin, not a mixed bed that separated. (I have to wonder if maybe as one of the resins gets exhausted, its density changes more than the other leading to a greater chance of separation.)

I'm not saying I know just because I can't figure it out.

I've heard of systems that run separate beds, presumably to recharge the resin without removing from the canister. That's what I am considering, but don't want to shoot myself in the foot.
Buckeye Hydro
05/26/2015, 04:32 AM
I don't think it really matters if they are physically in two different containers, or are in the same container. They are both separate beds. In my experience I see the last stage in a separate bed DI being a mixed bed.

Also be aware that the ratio (volume) of anion to cation resin in a mixed bed may not be 1:1

Russ
salty joe
05/27/2015, 04:47 AM
In my experience I see the last stage in a separate bed DI being a mixed bed.



Russ

So that would be a cation canister and an anion canister followed by a mixed bed canister?
I can't wrap my head around why a mixed bed would outperform separate beds.
Buckeye Hydro
05/27/2015, 05:18 AM
So that would be a cation canister and an anion canister followed by a mixed bed canister?

Right. You can think of a mixed bed as a very high number of separate beds right next to each other - where the water goes through them an enormous number of times.
sleepydoc
05/27/2015, 01:17 PM
1. DI Resin from EBAY
2. exhausting quickly.

I wonder if No. 1 and No. 2 are related.

:lmao:
skeeter_ca
05/27/2015, 02:02 PM
Then I insert the resin canister afterward.

Say What! You remove the DI resin canister from the filter housing, flush it and then reinstall it. Is the resin canister left out of the housing for very long? Don't you have a valve to divert the first portion of the water?
Buckeye Hydro
05/27/2015, 02:14 PM
Why is my DI Resin i bought from eBay being used up so quickly?! My TDS IN is only 5, yet - its fully used up within 40 gallons. My pressure great (50-60), I avoid TDS Creep and always let it drain in the waste line for 15 minutes to make sure the TDS IN level is brought down to the lowest. Then I insert the resin canister afterward.

15 minutes is waaaaaaaaaaaaaaaaaaay overkill for avoiding the effects of TDS creep. Here's some data that shows TDS creep effluent from75 gpd membranes. It was over by about 60 seconds. Yours may vary a bit from this, but no way it's 15 minutes.

http://i224.photobucket.com/albums/dd293/BuckeyeFS/Graphs/TDSCreep_zps2523e7a5.png

Rather than pulling the housing off twice and taking the DI cart out, and then putting it back in, consider a simple 3-way diverter valve:
http://i224.photobucket.com/albums/dd293/BuckeyeFS/Fittings/valves/3-wayvalve_zps9e9fda10.png

Russ