Another Ro/Di question

[tmccaffery]

I heard you shouldnt use carbon block for well water instead use another sediment filter; So I was thinking of doing this..

1st stage 5 micron sediment

2nd stage 0.5 micron sediment

3rd stage membrane

than degass it and use aqualifter pump to DI after 24hrs.

Thoughts?

My house TDS is 438; my RO TDS is 19 and my resin is being used up pretty quickly so I am guessing have high co2 and high particles in water supply.

 

[Uncle99]

Never heard of carbon block, but if it's a block, that's not going to efficiently remove toxins
I always, always use granulated carbon in the process, as well as the DT...

 

[thegrun]

I would recommend contacting the guys over at Buckeye Hydro for a good informed answer. I was not aware of issues with using a carbon block filter with well water, but I'm sure that Buckeye will steer you in the right direction. http://www.buckeyehydro.com/

 

[nereefpat]

I would still run one carbon block. A lot of cities use groundwater wells for municipal water.

Make sure the pore size on the sediment filter is at least as small as the pore size on the carbon block.

Your rejection rate for the RO is about 95%. You should be able to do better than that. Maybe more feed pressure? The 19 TDS on the RO permeate is too high, and will eat up your DI resin.

I can't help you much with the CO2 issue, if that's what it is. I would think there would be a way to test for it though.

 

[LQT]

Never heard of carbon block, but if it's a block, that's not going to efficiently remove toxins
I always, always use granulated carbon in the process, as well as the DT...

OP is talking about an RODI unit... not reef tank filtration.

 

[tmccaffery]

Got you; I will contact Buckeye.

 

[Buckeye Hydro]

Yes - still use a carbon block if you have well water - think of it as a very low cost insurance policy. I'd not worry about using a top shelf block, but go with a 5 micron block and call it good.

 

[Buckeye Hydro]

I would still run one carbon block. A lot of cities use groundwater wells for municipal water.

Make sure the pore size on the sediment filter is at least as small as the pore size on the carbon block.

Yes!

 

[hkgar]

I am also on a well and was burning through DI resin monthly. I now go from ro membrane to a 50+ gallon brute, degass for 24-48 hours and pump back through the DI resin and a canister of DI resin now last for more than a year.

I am not sure a Aqua lifter pump will provide enough pressure to get through the DI. I use a small MaxiJet pump.

Consider a Spectrapure 99% RO membrane. My well water after the softener is 210 and 2 after my RO membrane.

 

[Buckeye Hydro]

Fun fact to know and tell. As of several years ago Filmtec changed the factory spec on their 75 gpd membranes. Used to be 98%. Has been 99% for several years.

 

[Uncle99]

OP is talking about an RODI unit... not reef tank filtration.

I would like to continue my stupid answer to the carbon block thing...
I have a 6 stage RODI unit two of which are canisters which contain a carbon insert...
Is the carbon block just a term for carbon removal?

 

[LQT]

The carbon block allows for water to evenly flow through it (unlike GAC cartridges), removing chemicals (like chlorine) and organics that would otherwise damage your RO membrane. Remember, all of the prefilters in RODI units, like the sediment cartridge and carbon blocks serve to protect the RO membrane, prolonging its efficiency and useful life.

 

[Uncle99]

Thank you LQT for taking the time to explain that to me.
I always just assumed carbon was carbon, but not exactly.
Appreciated....

 

[Buckeye Hydro]

Carbon blocks are extruded PAC. Powdered Activated Carbon has particle sizes much smaller than GAC - Granular Activated Carbon. The smaller the particle size, the greater the surface area, and the better the treatment. If you see a vendor with standard GAC cartridge prefilters on an RODI unit, you might want to take your business elsewhere.

Russ

 

[nereefpat]

Carbon blocks are extruded PAC. Powdered Activated Carbon has particle sizes much smaller than GAC - Granular Activated Carbon.

Interesting.

 

[hkgar]

I think it is called a block because it "blocks" certain things from getting through

 

[Buckeye Hydro]

It's called a block because the PAC is extruded into a solid block form - different than the old granular form.

Russ

 

[Sisterlimonpot]

OP,
The main purpose of the carbon block (Russ correct me if i'm wrong) is to remove chlorine that municipalities add to the drinking water to disinfect and remove pathogens that may be present in the water. I would guess that the train of thought of why you were told not to use a carbon block is because you wouldn't have chlorine present in your water.

I have seen homes with wells that have a system that pump the water from the well, injects chlorine and then stores it in a tank for use when needed. I don't know how common those are nor if you have something like that but something that people need to be aware of when they're being told not to use a carbon block.

As stated above by many people, it's better to have it because chlorine can destroy your RO membrane.

 

[Uncle99]

Thanks to all, learn something new every day!