Air Water Ice vs Bulk Reef Supply

Neither, both use high micron nominal rated filters.
Chheck out the 0.5 micron absolute rated filters on sale here:
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I would also eliminate the dual carbons since a single carbon is more than sufficient if preceded by a good low micron sediment filter that protects the carbons billions of tiny pores that adsorb chlorine. Use the extra housing for a second DI filter that will really give you some bang for your buck.

 

Okay so I've done a little bit of reading and it seems like you guys are right. I have decided on a 0.5 micron sediment filter. How many microns would you guys recommend for a single carbon filter?

My TDS is reading about 30. I purchased the unit about a year ago with all new filters. I haven't replaced anything. I should have researched more. The RO membrane is supposed to last about 3-5 years. Do you think the membrane is done for? I am thinking about ordering a new sediment filter, carbon filter, and DI cartridge. I would then measure the rejection rate of the membrane to determine its condition.

It seems like most people don't realize that just because the TDS reads 0, that doesn't mean their filters are fine. Thanks reeron for getting me to research it. I was just about to buy the Air Water Ice package before you said that.

 

You will want a 0.5 or 0.6 micron carbon block to match the sediment filter.

To find out the condition of your RO membrane you need to test the tap water TDS and the RO only TDS to determine the rejection rate. You will also want to find out the water temperature, water pressure at the membrane and calculate your exact waste ratio to see if the membrane production rate has dropped off due to fouling or plugging. When membranes begin to fail the TDS may go up but more often its the production rate that drops off first then the membrane starts to get tears failures in the fabric and TDS goes up.

Check your tap water and RO only TDS first and determine the rejection rate, then get the temp and pressure and measure the waste ratio and all that together will tell you if you need to replace the membrane. Probably not but you really want to know all that information to give you a good starting point you can record for future testing.

 

Where does water temp come into this calculation? Lol is there a master calculation for something like this? And is there a certain temp I should be using? I usually use cold water.

 

Two things have a major effect on a membranes output, pressure and temperature.
Membranes are actually rated at up to 150 psi or higher, its the housings and components that are the weak link.
Most major membrane manufacturers rate their membranes production rate and rejection rate at 77 degrees F water temp. That really doesn't mean much, its just a baseline so you can compare one against another. What is critical though is membranes cannot take anything over 113 degrees or it can melt the TFC fabric and glues that hold it together. Its best to use strictly cold water as trying to blend or temper the water often leads to problems and melted membranes. Remnember being in the shower and someone flushes the toilet or starts the washing machine? You get your tush scalded and thats the same thing that melts a membrane.

Go to the top of the page here, www.buckeyefieldsupply.com , and you can play with the calculator which shows the effects temperature and pressure have on a membrane.
You can also download the worksheet here:
http://www.spectrapure.com/CALC-FORMULA.pdf

and see how your membrane stacks up.

One thing to consider is cold water treats better, gives you lower TDS and extended DI life, than warm water so to overcome the effects of cold water its better to boost pressure rather than warming the water.

 

Thanks you are being really helpful. Since you seem pretty knowledgable I hope you don't mind answering a couple more questions..

Any recommendations about the DI resin? Is the color-changing feature necessary if I have a TDS meter? And what is the difference between an air-filled and glycerin-filled pressure gauge?

 

I much prefer Spectrapure DI resins because they blend their own based on thousands of hours of bench and real world beta testing. The SilicaBuster will last 2-30% longer than any other mixed bed resins and the MaxCap used in conjunction with a downstream DI in a dual DI situation will them last at least 3.5x longer. I used to use normal nuclear or semiconductor grade mixed bed resins and no matter where I bought it or how fresh it was I couldn't get more than 150 gallons per 20 oz cartridge. On my first MaxCap SilicaBuster setup the first SilicaBuster lasted 830 measured gallons, the second over 1000 and its been like that ever since. The MaxCap cartridge lasts over 3000 gallons! And I'm in Phoenix with a tap water TDS over 600 most times.

Color changing resins can be unpredictable, they may change in streaks, top to bottom, bottom to top, not at all, all at once etc. Use the TDS meter if you want accuracy since DI resins start to release weakly ionized substances even before they are exhausted or turn colors.

A glycerin or oil filled gauge will not flutter or slam the needle into the stop with rapid pressure changes or pulsations and is normally used in a pumped water situation. An air filled gauge has no damping for those situations but is fine for most applications.

 

Do you know if the Maxcap cartridge will fit in my air water ice system? The system seems pretty standard. Since it is a 5-stage - I will have one extra space by removing one of the two carbon filters. Did you mean that I should put the silicabuster in the extra space, and the maxcap DI cartridge in the space where I have my current DI cartridge? Or did you mean the silicabuster in addition to two DI cartridges? Sorry that I am a little confused. Also, how will I know when it is time for a new silicabuster cartridge? This is adding up to a lot of money.. I guess it will save me money in the long run though since it will last much longer.

 

The MaxCap DI is not intended as a stand alone DI. It is a roughing filter or "pre DI" cartridge intended to be used in a dual DI situation with a mixed bed cartridge downstream.

The long term cost savings is tremendous. Both cartridges are on sale in the October flyer.

Here is an article they published recently:

Spectrapure Tech Support is distributing this reference tutorial to assist customers that use De-Ionization Filters as part of their water purification systems. Included is a brief explanation of fundamental De-Ionization science, various DI cartridge configurations, and some recommended techniques to aid in determining DI cartridge exhaustion. This information will help you to better understand general DI theory and the basic DI cartridge types available, and will assist you in the cartridge selection process.

Using and Configuring SpectraPure De-Ionization Cartridges

SpectraPure has an extensive line of DI cartridges and bulk resins, mixed and layered, for application-specific uses. Most de-ionizing (DI) cartridges are a mixture of Anion and Cation resin in specific-to-the-application ratios. Cation resin holds a preponderance of H+ ions on its surface while Anion resin holds a similar quantity of OH- ions. When positive-charged impurities, i.e. Sodium, (Na+) are exposed to Cation resin, the impurities will "stick" to the resin, knocking off an H+ ion to travel on downstream. Likewise, a negative-charged ion, i.e. Chloride, (Cl-) will "stick" to Anion resin, knocking off an OH- ion. If the resin mixture ratio is correct, the H+ and OH- ions will combine to recreate H20 molecules that will combine with the rest of the already-pure water that travels through the resin beds. Too much active Anion resin and the water will have a higher-than-neutral pH. Too much active Cation and the water will be lower-than-neutral pH.

Almost all resins can be provided as Color-Indicating and Non-Indicating. This refers to a change in color of some portion of the resin in response to resin consumption / expiration. Color indication is typically used as a less expensive alternative to electronic water quality monitors such as inline or hand-held TDS meters. No further distinction will be made in this discussion.

The most common DI cartridge is the Mixed-Bed. Different ratios are used for different applications, but most of the Mixed-Bed resin we formulate is made especially for Reverse Osmosis water. Mixed-Bed cartridges can be used solo, as a pair, or after a specialty cartridge.

Special cartridges include the All-Anion Silica-Free (DI-SF-CI-10) and the half-Anion / half-Cation Ammonia-Remover (DI-AR-CI-10). This pair has been used for years (since 2000) in our SP2000 RO/DI system. A Mixed-Bed can also be positioned after a Silica-Free cartridge.

The SilicaBuster was the logical improvement over the above combination. It is 1/3 Anion and 2/3 Mixed-Bed with the water meeting the Anion first and then passing through the Mixed-Bed. For a single cartridge system, this one is hard to beat for aquarists' concerns.

We have developed a unique and proprietary cartridge called the MaxCap DI. It can be found in our five stage MaxCap RO/DI System. This cartridge has a much-improved capacity over a typical Mixed-Bed, but is not designed for single cartridge systems; a SilicaBuster or Mixed-Bed cartridge should ALWAYS follow it. This combination will produce more and purer water than two Mixed-Bed cartridges in series. Sometimes, for larger commercial systems, we may have a 20-inch cartridge full of Anion (DI-SF-CI-20) followed by one or two 20-inch Mixed-Bed cartridges. Other combinations are possible after consulting with our Engineering Staff.


Single Stage:

Mixed-Bed (indicating and non-indicating)
-Or-
Silica Buster (indicating and non-indicating)
When to change:
In general, when the TDS meter indicates a greater than 001 reading, it is time to change your single stage DI filter. Alternatively, when your color changing DI cartridge has nearly completed changing color (75-80%), it is time to change your single stage DI filter.


Dual Stage:
MaxCap - SilicaBuster
-Or-
MaxCap - Mixed-Bed
When to change:
When the TDS after the MaxCap reads half of the TDS before the MaxCap, replace the MaxCap. When the TDS after the second DI indicates a greater than 001 reading, it is time to change that DI filter. Alternatively, when the color changing DI cartridge has nearly completed changing color (75-80%), it is time to change that DI filter.

Mixed-Bed - Mixed-Bed (For special applications, this configuration may be used.)
When to change:
When #1 becomes exhausted (either by color change or by a TDS meter's probe located between the cartridges), move #2 to #1 and put a new cart in #2.

Legacy Configuration:
SilicaFree - Ammonia Removal
When to change:
The SF will change color, replace after 75-80% change. The AR should use a TDS meter to indicate a greater than 001 reading, or you can monitor the half of the cartridge that changes color.

Three Stages:
A third stage is seldom used unless there is a severe CO2 problem.�� Then a SilicaFree can be put in front of a Dual Stage configuration.
When to change:
The SF will change color, replace after 75-80% change. For the remaining two stages, monitor as indicated above.

Four Stages:
MaxCap - MaxCap - SilicaBuster - SilicaBuster
-Or-
MaxCap - MaxCap - Mixed-Bed - Mixed-Bed
When to Change:
When #1 becomes exhausted, move #2 to #1 and put a new cart in #2. Likewise for #3 and #4.

Four Stage Laboratory Systems:
MB/ULTOC - MB/ULTOC - MB/UPC - MB/ORG
When to change:
Use a lab-quality resistivity meter. When the resistivity drops below a specified set point (as determined by the user), all four cartridges should be replaced. If the resistivity is above the set point but substances such as organics exceed specifications, replace the ORG and ULTOC cartridges. Call Tech Support for assistance.
Legacy Configuration:
SilicaFree - SilicaFree - Am. Removal - Am. Removal
When to change:
When #1 becomes exhausted, move #2 to #1 and put a new cart in #2. Likewise for #3 and #4.

 

Thanks, that answered my questions. I just calculated how much money I would save by doing this. Lets just say that I am too embarrassed to admit how much money I've wasted. I guess the quality of the RO membrane is also a factor. But I don't even know if mine is bad yet so thats impossible to calculate. For future reference, in case you switch to a different forum or something, what type of RO membrane do you recommend?