RO/DI from Ebay: ONE review inside!

cabrego · 08/06/2008, 08:09 AM

Hey all,

I am finally making my baby steps in becoming a true reefer. Thus, today I am scheduled to receive my RO/DI unit from Ebay.

Yes it is an ebay unit....I know there is much controversy about buying ro/di units from ebay sellers. That is why I have decided to make this threat.

I will keep you posted,

http://cgi.ebay.com/REEF-DRINKING-RO...QQcmdZViewItem

Here is the unit in question...

cabrego · 08/06/2008, 02:53 PM

Ok, I received the package around noon time today. I purchased the item online July 30, so it took about 6 days to get here from the time that I "bought it now". Package came from california.

Here is the contents of the package.

The kit has been packed very well and complete with good instructions. I was able to install this unit bought as a single purchase, no trips to the store or using additional hardware was required.

Location

I choose to keep the unit under the sink, this will allow me to easily make use of the RO water for cooking and drinking.

ID cold water line

Install this guy

This was by far the hardest part of the installation. It took 3 or 4 installs before I figured out how to install it without leaking. I will admit I do not have mcuh plumbing experience, but I underestimated how tight, it should be 3 times.

DRAIN

Leak Test

Whew no leaks!!!!
Final Product

Overall I am happy with the unit so far, the quality is is good, no leaks, the true test of course is the water quality.

Esquare · 08/06/2008, 03:08 PM

What size fish tank do you have?

I have a similar system from the same guys and have been happy with it. Mine is not set up with the RO drinking water tank though. Also, my Dt is only 54 gallons and the overall system is only about 120 gallons so it's not a big load on the ro/di filter.

snorvich · 08/06/2008, 03:13 PM

TDS meter? Output reading?

cabrego · 08/06/2008, 03:20 PM

This is to support a 90 gallon tank. This is a 100 GPD unit, so I am sure it will be adequate.

My tap water TDS is around 190 or so, I am still flushing the membrane and filters so I will not be able to give numbers till later this evening.

reefrick.M · 08/06/2008, 04:02 PM

I bought one, although different model than yours from Filter Direct almost 3 years ago. Works great !!! Paid 100.00 for it. Zero TDS until the DI resin changes color, which for me is about 6 months. Then once a year I change out everything. For the price you can't beat it.

Patis46 · 08/06/2008, 05:16 PM

I just got almost the same one you did. Except different vendor.
I did some research on filters and membranes and found out that the vendor i checked with had the right membrane brand that was included with the system. 100gpd. 0 TDS. Un filtered is 210. The valves and housings are probably made by just one or two companies..So hard to go wrong there. Yes there cheaper than some of the big talked about brands but work just as good if you do a little research first.
Pat

cabrego · 08/06/2008, 05:28 PM

Quote:

Originally posted by Patis46
I just got almost the same one you did. Except different vendor.
I did some research on filters and membranes and found out that the vendor i checked with had the right membrane brand that was included with the system. 100gpd. 0 TDS. Un filtered is 210. The valves and housings are probably made by just one or two companies..So hard to go wrong there. Yes there cheaper than some of the big talked about brands but work just as good if you do a little research first.
Pat

What membrane is included in your unit?

I should be able to give a tds update shortly. Should I just dump out the first 5 gallons and then test the tDs?

Patis46 · 08/06/2008, 06:32 PM

From what i understand. The big name brands are all close to the same Dow GE and the like.
Mine was a Dow Filmtech 100gpd and the complete unit was $119 for the 6st setup with 3.2 gal tank+ 40 something shipping.

Also i notice in your pics your discharge line is after you trap. In my directions it said not to put it there. In the event of a backup sewer water could contaminate the unit. Highly unlikely but yakneverknow.
Pat

cabrego · 08/06/2008, 07:09 PM

Quote:

Originally posted by Patis46
From what i understand. The big name brands are all close to the same Dow GE and the like.
Mine was a Dow Filmtech 100gpd and the complete unit was $119 for the 6st setup with 3.2 gal tank+ 40 something shipping.

Also i notice in your pics your discharge line is after you trap. In my directions it said not to put it there. In the event of a backup sewer water could contaminate the unit. Highly unlikely but yakneverknow.
Pat

What is the trap?

magnoliarichj · 08/06/2008, 07:26 PM

convert all those fitting to john guest ones.

cabrego · 08/06/2008, 07:27 PM

Tap water=190

RO/DI=0-1 ppm

Drinking line- which I believe is ro/di/then taste filter- so far it is at around 45-50. This number seems to be lower everytime i test it.

I am not sure why they would push water through the ro/di/ then add that much ppm with the taste filter.

cabrego · 08/06/2008, 07:28 PM

Quote:

Originally posted by magnoliarichj
convert all those fitting to john guest ones.

John Guest?

JNye · 08/06/2008, 08:05 PM

Quote:

Also i notice in your pics your discharge line is after you trap. In my directions it said not to put it there. In the event of a backup sewer water could contaminate the unit. Highly unlikely but yakneverknow.
Pat

Hooking it up before the trap does not eliminate this potential problem. Personally I would never hook a drinking water line up directly to a sewer line. Would you believe there is laws against this?

Zestay · 08/06/2008, 08:38 PM

i have pretty much the same system ( water general ) but mine has 2 out puts.
one is ro -> carbon filter for taste that is on my sink
the other is DI

i have my dual inline tds meter hooked up to each of the out puts. my RO is 8
DI is 0

now my filter did sit unused for about 3 months and i noticed my TDS was up to about 30 untill i drained the tank and let it refil with fresh water than it was back down to 8 and 0

jimnrose · 08/06/2008, 08:41 PM

Cabrego, thanks for sharing your purchase. I'll be making a decision shortly and will keep this supplier 'on the short list'.The options for the dual TDS meter and float switch will also be ordered.
Thanks, Jim

cabrego · 08/06/2008, 09:14 PM

Quote:

Originally posted by poo-tang
Hooking it up before the trap does not eliminate this potential problem. Personally I would never hook a drinking water line up directly to a sewer line. Would you believe there is laws against this?

I am a bit confused, what is a trap where did I install my drain line?

I really only had two options for installing the drain line,

1. Where it is installed- which i believe to be the primary and only drain from the disposal.

2. The other option is not feasible, which is the dishwashing hose.

All other lines, were hard brass feed lines. Anyone care to elaborate?

Jim, no problem. I purchased a stand alone Hanna TDS 3 from a different ebay vendor for 20 dollars shipped.

I am on a tight budget so, I am cherry picking as much as I can. So far for 150 shipped I can't complain and we don't have to by bottled water anymore.

Zestay, this is in fact the unit you are talking about with 2 outputs.

AZDesertRat · 08/06/2008, 10:39 PM

Plumbing codes say an RO drain should be hooked up using an air gap faucet and must be plumbed to the sink side of the P trap. You have your hooked on the sewer side of the P trap but it does not appear you had any choice. This is not a good installation if you have a choice. You should also move the drain down to the side of the pipe so sewer gas does not rise up and get into the line.
The true measure of the efficiency of a RO or RO DI system is the membrane efficiency not the DI efficiency, any unit should get it down to 0 TDS, at least for a short time. This is where the cheaper less efficient systems fall down, some drastically. You got the 100 GPD Dow Filmtec membrane which is probably the absolute worst possible choice of all the membranes available. If you do a little research you will find it is not actually a reverse osmosis membrane at all but is classified as a nano filter which is not approved nor intended for drinking water in the US. It carries a completely different ANSI/NSF rating which states " Pool and Spa Use" right on the label.
The difference is 90% rejection vs 96-98% rejection which is a major difference. Consider for every 2% you increase your membranes efficiency you DOUBLE the life of your DI resin. Given that if you had opted for the 75 GPD trur RO mermbrane your DI would last you about four times as long per cartridge. Also if you had opted for a true 20 oz vertical DI canister and cartridge you would get the additional benefit of bottom up filtration with no short circuiting or channelling which you wil find is a problem with the hollow horizontal tubes with 6-9 oz of resin in them.

Post your tap water TDS and RO only TDS numbers then keep track of how long your DI lasts and keep this thread alive. Unfortunately experience tells me what appears to be a good deal soon becomes not such a good deal over time and the costs soon exceed what a good reef quality unit would have cost to begin with. For $169 you could have had a reef quality system with a 75 GPD Dow 98% RO membrane, 0.5 micron prefilter, 0.6 micron Matrixx+1 20,000 gallon carbon block, true vertical 20 oz DI cansiter and refillable cartridge full of fresh nuclear grade resin, a RO bypass valve, an inline pressure gauge, a name brand hand held TDS meter, an adjustable flow restrictor, clear housings, a flush valve, all John Guest speed fittings ....... More than worth the difference.

Don't mean to be harsh but this comes up all the time and they still are not the value they seem to be. Add up the cost of all those DI replacements plus the cost of a replacement membrane in 18 to 24 months. Better prefilters and carbons greatly increase the life of the membrane, 10 years is not unheard of with high quality replacements where 24 months of use is common with low quality filters.

cabrego · 08/07/2008, 06:17 AM

Quote:

Originally posted by AZDesertRat
Plumbing codes say an RO drain should be hooked up using an air gap faucet and must be plumbed to the sink side of the P trap. You have your hooked on the sewer side of the P trap but it does not appear you had any choice. This is not a good installation if you have a choice. You should also move the drain down to the side of the pipe so sewer gas does not rise up and get into the line.
The true measure of the efficiency of a RO or RO DI system is the membrane efficiency not the DI efficiency, any unit should get it down to 0 TDS, at least for a short time. This is where the cheaper less efficient systems fall down, some drastically. You got the 100 GPD Dow Filmtec membrane which is probably the absolute worst possible choice of all the membranes available. If you do a little research you will find it is not actually a reverse osmosis membrane at all but is classified as a nano filter which is not approved nor intended for drinking water in the US. It carries a completely different ANSI/NSF rating which states " Pool and Spa Use" right on the label.
The difference is 90% rejection vs 96-98% rejection which is a major difference. Consider for every 2% you increase your membranes efficiency you DOUBLE the life of your DI resin. Given that if you had opted for the 75 GPD trur RO mermbrane your DI would last you about four times as long per cartridge. Also if you had opted for a true 20 oz vertical DI canister and cartridge you would get the additional benefit of bottom up filtration with no short circuiting or channelling which you wil find is a problem with the hollow horizontal tubes with 6-9 oz of resin in them.

Post your tap water TDS and RO only TDS numbers then keep track of how long your DI lasts and keep this thread alive. Unfortunately experience tells me what appears to be a good deal soon becomes not such a good deal over time and the costs soon exceed what a good reef quality unit would have cost to begin with. For $169 you could have had a reef quality system with a 75 GPD Dow 98% RO membrane, 0.5 micron prefilter, 0.6 micron Matrixx+1 20,000 gallon carbon block, true vertical 20 oz DI cansiter and refillable cartridge full of fresh nuclear grade resin, a RO bypass valve, an inline pressure gauge, a name brand hand held TDS meter, an adjustable flow restrictor, clear housings, a flush valve, all John Guest speed fittings ....... More than worth the difference.

Don't mean to be harsh but this comes up all the time and they still are not the value they seem to be. Add up the cost of all those DI replacements plus the cost of a replacement membrane in 18 to 24 months. Better prefilters and carbons greatly increase the life of the membrane, 10 years is not unheard of with high quality replacements where 24 months of use is common with low quality filters.

First of all thanks for the reply, I know you have lots of experience in this area. I am just a laymen when it comes to plumbing issues, this is my first "plumbing job", so I am not sure about the air gap issues..if an air gap is required for install, it seems like it should be included in all systems.

Now, i will tell you where I think you are wrong:

1. You quoted a "100 GPD Dow Filmtec membrane". The actual membrane is a 100 GPD GE desal. Which is suitable for drinking water etc. Therefore, all your statistics do not reflect the unit purchased.

2. The 169 is not a fair comparison because I also received a storage tanks, faucet adaptor, etc.

I did a good amount of research before I bought this unit. Because i do not have 2 or 3 hundred dollars. I concluded that this is a good middle ground. If i have to replace the prefilters in 12 months instead of 2 years, I am ok with that. I can always upgraded the filters as needed.

AZDesertRat · 08/07/2008, 07:49 AM

OK, the 100 GPD GE Desal is almost identical to a 75 GPD Dow. Dow says 75 GPD at 50 psi, GE says 100 GPD at 65 psi, overlay the graphs and they are almost the same.
You need to replace the prefilter and carbon at 6 month intervals like clockwork, never ever wait a year. My concerns are still valid in the quality of the filters your unit contains, they are bottom of the barrel and just slightly more effective than a screen door as far as filtration. On your first filter change go to a different vendor and get a minimum of a 1 micron prefilter, a 0.5 or 0.2 micron absolute rated filter would be better and make your membrane last much longer. Same goes for the carbon, first there is no need for two carbons especially if you have one good one. The ones that come with that unit are good for about 1000 total gallons of water before they are spent, a single good 0.5 micron Chlorine Guzzler will last up to 20,000 gallons and also act as a secondary prefilter again to protect the membrane.
Personally i would not drink any water from the system until I could find a better way to hook thefaucet anddrain up. You want that air gap for your health and safety. There is a reason for plumbing codes. The possibility of cross connection is very real and the results can be catastrophic even deadly. I have seen sickness due to improperly installed systems more than once and it takes a long time to get back to normal health if at all. If they don't offer it, go to a different supplier for an approved air gap faucet and move the drain to another location.

The $169 is a great comparison since for the $169 you receive twice the filter. Add up the cost of the hard goods, tank, faucet, membrane and a few odds and ends and it should make you mighty suspicious. If a name brand membrane sells for $30-40 everywhere on planet Earth, a tank is going to run you at least $30 or $40, the faucet is $5. You are already at $85 so that does not leave much for them to work with and supply quality parts and still make a profit. Most of the components are Chinese imports that do not carry any NSF or plumbing code ratings and are of inferior quality.
Again good units use name brand housinghs like Amatek and name brand fittings like John Guest along with name brand filters like Matrixx. Its just not the same and has been proven over and over. They made another sale though and thats all that counts to them!

cabrego · 08/07/2008, 08:32 AM

Well I understand that you are passionate about quality, and I am too. I just can not afford to spend the money it takes.

Your conern about the air gap is a valid one, it is only an issue because of my own lack of experience with RO installs. The last thing I want to do is risk contaminations of any kind.

I do have to call you out with a math problem you pose.

You say: "You need to replace the prefilter and carbon at 6 month intervals like clockwork, never ever wait a year."

followed by " The ones that come with that unit are good for about 1000 total gallons of water before they are spent".

I would have to go through 166 gallons every month in order to spend my filters in 6 months according to your numbers. More realistic is probably 60 or 70 gallons a month as a high estimate.

AZDesertRat · 08/07/2008, 08:48 AM

You don't change the prefilter and carbon because they are spent, you change them to lessen the likelyhood of bacteria and viruses growing on them. This is another health issue. Now, if you use a 0.2 micron absolute rated prefilter and Chlorine Guzzler carbon which are small enough to trap 99% of viruses and bacteria then and only then you can safely extend your filter runs if you kep track of pressure drop across the filter array and a low level chlorine test kit to monitor chlorine break thru on the carbon. This is a pain for most people so the 6 month method is recommended.
You need to understand all the water that eneters the filter goes through the prefilter and carbon, not just the product or "good" water. In a normal system at 4:1 waste ratio that 1000 gallons equates to 800 waste gallons and only 200 total good gallons. Figure that over a 6 month period and its only 33 gallons of good water a month before they are exhausted. Thats another thing the e bay vendors don't tell you.
It is actually much less than that when you are using a pressure tank system. When pressure starts to build up in the tank the waste ratio will actually go as high as 20:1 for a good amount of time before the autoshutoff valve finally shuts it off. A permeate pump can help this situation and is recommended with pressurized systems.

Like I said it looks and sounds good until you really look into it.

cabrego · 08/07/2008, 09:12 AM

I see, you have shared lots of good information. When the time does come to replace prefilters I will definately look into upgrading to the higher quality units that you describe.

Thanks!

second_decimal · 08/07/2008, 09:59 AM

you should install a 1lb check valve for the drain. it would at least help prevent backwash etc. and extend the life of the filters / keep things cleaner since you dont have another place to install the drain. another thing to keep in mind, is that when you are ready to replace filters, you shoudl be able to replace them with high quality ones from a non chinese source. they are all universal to my understanding. i like spectrapure myself but there are others that compare.

AZ correct me if am wrong here.

AZDesertRat · 08/07/2008, 10:05 AM

Check valves may help but they are not approved backflow prevention devices and will not take the place of an air gap.

I am also a fan of Spectrapure products, they have untold thousands of hours of lab and real world testing data on all their filters and will not sell anything no matter how small unless it lives up to their standards. They beta test prefilters in some of the worst water conditions in the country before they even bring them to market.

08/06/2008, 08:09 AM	#1
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	RO/DI from Ebay: ONE review inside! Hey all, I am finally making my baby steps in becoming a true reefer. Thus, today I am scheduled to receive my RO/DI unit from Ebay. Yes it is an ebay unit....I know there is much controversy about buying ro/di units from ebay sellers. That is why I have decided to make this threat. I will keep you posted, http://cgi.ebay.com/REEF-DRINKING-RO...QQcmdZViewItem Here is the unit in question...

08/06/2008, 02:53 PM	#2
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	Round 1: Installation Ok, I received the package around noon time today. I purchased the item online July 30, so it took about 6 days to get here from the time that I "bought it now". Package came from california. Here is the contents of the package. The kit has been packed very well and complete with good instructions. I was able to install this unit bought as a single purchase, no trips to the store or using additional hardware was required. Location I choose to keep the unit under the sink, this will allow me to easily make use of the RO water for cooking and drinking. ID cold water line Install this guy This was by far the hardest part of the installation. It took 3 or 4 installs before I figured out how to install it without leaking. I will admit I do not have mcuh plumbing experience, but I underestimated how tight, it should be 3 times. DRAIN Leak Test Whew no leaks!!!! Final Product Overall I am happy with the unit so far, the quality is is good, no leaks, the true test of course is the water quality.

08/06/2008, 03:08 PM	#3
Esquare Registered Member Join Date: Jan 2008 Location: Lorain, Ohio Posts: 1,954	What size fish tank do you have? I have a similar system from the same guys and have been happy with it. Mine is not set up with the RO drinking water tank though. Also, my Dt is only 54 gallons and the overall system is only about 120 gallons so it's not a big load on the ro/di filter. __________________ Eddie Current Tank Info: 40 Breeder with Dwarf Lionfish

08/06/2008, 03:13 PM	#4
snorvich Team RC member Join Date: Aug 2005 Location: Outlander Posts: 40,953 Blog Entries: 46	TDS meter? Output reading? __________________ Warmest regards, ~Steve~

08/06/2008, 05:16 PM	#7
Patis46 Registered Member Join Date: Jul 2008 Location: Sandpoint ID Posts: 44	I just got almost the same one you did. Except different vendor. I did some research on filters and membranes and found out that the vendor i checked with had the right membrane brand that was included with the system. 100gpd. 0 TDS. Un filtered is 210. The valves and housings are probably made by just one or two companies..So hard to go wrong there. Yes there cheaper than some of the big talked about brands but work just as good if you do a little research first. Pat __________________ Wife said..Honey i think you need a hobby. Current Tank Info: 55G with nothing but SW in it;) 20G sump, skimmer, 6X54 T5-HO 48in light

08/06/2008, 03:20 PM	#5
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	This is to support a 90 gallon tank. This is a 100 GPD unit, so I am sure it will be adequate. My tap water TDS is around 190 or so, I am still flushing the membrane and filters so I will not be able to give numbers till later this evening.

08/06/2008, 04:02 PM	#6
reefrick.M Registered Member Join Date: Oct 2005 Location: MA. Posts: 193	I bought one, although different model than yours from Filter Direct almost 3 years ago. Works great !!! Paid 100.00 for it. Zero TDS until the DI resin changes color, which for me is about 6 months. Then once a year I change out everything. For the price you can't beat it.

08/06/2008, 06:32 PM	#9
Patis46 Registered Member Join Date: Jul 2008 Location: Sandpoint ID Posts: 44	From what i understand. The big name brands are all close to the same Dow GE and the like. Mine was a Dow Filmtech 100gpd and the complete unit was $119 for the 6st setup with 3.2 gal tank+ 40 something shipping. Also i notice in your pics your discharge line is after you trap. In my directions it said not to put it there. In the event of a backup sewer water could contaminate the unit. Highly unlikely but yakneverknow. Pat __________________ Wife said..Honey i think you need a hobby. Current Tank Info: 55G with nothing but SW in it;) 20G sump, skimmer, 6X54 T5-HO 48in light

08/06/2008, 07:26 PM	#11
magnoliarichj Registered Member Join Date: Mar 2007 Location: florida west coast Posts: 1,455	convert all those fitting to john guest ones.

08/06/2008, 07:27 PM	#12
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	WATER TEST Tap water=190 RO/DI=0-1 ppm Drinking line- which I believe is ro/di/then taste filter- so far it is at around 45-50. This number seems to be lower everytime i test it. I am not sure why they would push water through the ro/di/ then add that much ppm with the taste filter.

08/06/2008, 08:38 PM	#15
Zestay Registered Member Join Date: Sep 2006 Location: gainesville, FL Posts: 1,622	i have pretty much the same system ( water general ) but mine has 2 out puts. one is ro -> carbon filter for taste that is on my sink the other is DI i have my dual inline tds meter hooked up to each of the out puts. my RO is 8 DI is 0 now my filter did sit unused for about 3 months and i noticed my TDS was up to about 30 untill i drained the tank and let it refil with fresh water than it was back down to 8 and 0

08/06/2008, 08:41 PM	#16
jimnrose Registered Member Join Date: Feb 2008 Location: The Villages, Florida Posts: 1,093	Cabrego, thanks for sharing your purchase. I'll be making a decision shortly and will keep this supplier 'on the short list'.The options for the dual TDS meter and float switch will also be ordered. Thanks, Jim

08/06/2008, 10:39 PM	#18
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Plumbing codes say an RO drain should be hooked up using an air gap faucet and must be plumbed to the sink side of the P trap. You have your hooked on the sewer side of the P trap but it does not appear you had any choice. This is not a good installation if you have a choice. You should also move the drain down to the side of the pipe so sewer gas does not rise up and get into the line. The true measure of the efficiency of a RO or RO DI system is the membrane efficiency not the DI efficiency, any unit should get it down to 0 TDS, at least for a short time. This is where the cheaper less efficient systems fall down, some drastically. You got the 100 GPD Dow Filmtec membrane which is probably the absolute worst possible choice of all the membranes available. If you do a little research you will find it is not actually a reverse osmosis membrane at all but is classified as a nano filter which is not approved nor intended for drinking water in the US. It carries a completely different ANSI/NSF rating which states " Pool and Spa Use" right on the label. The difference is 90% rejection vs 96-98% rejection which is a major difference. Consider for every 2% you increase your membranes efficiency you DOUBLE the life of your DI resin. Given that if you had opted for the 75 GPD trur RO mermbrane your DI would last you about four times as long per cartridge. Also if you had opted for a true 20 oz vertical DI canister and cartridge you would get the additional benefit of bottom up filtration with no short circuiting or channelling which you wil find is a problem with the hollow horizontal tubes with 6-9 oz of resin in them. Post your tap water TDS and RO only TDS numbers then keep track of how long your DI lasts and keep this thread alive. Unfortunately experience tells me what appears to be a good deal soon becomes not such a good deal over time and the costs soon exceed what a good reef quality unit would have cost to begin with. For $169 you could have had a reef quality system with a 75 GPD Dow 98% RO membrane, 0.5 micron prefilter, 0.6 micron Matrixx+1 20,000 gallon carbon block, true vertical 20 oz DI cansiter and refillable cartridge full of fresh nuclear grade resin, a RO bypass valve, an inline pressure gauge, a name brand hand held TDS meter, an adjustable flow restrictor, clear housings, a flush valve, all John Guest speed fittings ....... More than worth the difference. Don't mean to be harsh but this comes up all the time and they still are not the value they seem to be. Add up the cost of all those DI replacements plus the cost of a replacement membrane in 18 to 24 months. Better prefilters and carbons greatly increase the life of the membrane, 10 years is not unheard of with high quality replacements where 24 months of use is common with low quality filters.

08/07/2008, 07:49 AM	#20
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	OK, the 100 GPD GE Desal is almost identical to a 75 GPD Dow. Dow says 75 GPD at 50 psi, GE says 100 GPD at 65 psi, overlay the graphs and they are almost the same. You need to replace the prefilter and carbon at 6 month intervals like clockwork, never ever wait a year. My concerns are still valid in the quality of the filters your unit contains, they are bottom of the barrel and just slightly more effective than a screen door as far as filtration. On your first filter change go to a different vendor and get a minimum of a 1 micron prefilter, a 0.5 or 0.2 micron absolute rated filter would be better and make your membrane last much longer. Same goes for the carbon, first there is no need for two carbons especially if you have one good one. The ones that come with that unit are good for about 1000 total gallons of water before they are spent, a single good 0.5 micron Chlorine Guzzler will last up to 20,000 gallons and also act as a secondary prefilter again to protect the membrane. Personally i would not drink any water from the system until I could find a better way to hook thefaucet anddrain up. You want that air gap for your health and safety. There is a reason for plumbing codes. The possibility of cross connection is very real and the results can be catastrophic even deadly. I have seen sickness due to improperly installed systems more than once and it takes a long time to get back to normal health if at all. If they don't offer it, go to a different supplier for an approved air gap faucet and move the drain to another location. The $169 is a great comparison since for the $169 you receive twice the filter. Add up the cost of the hard goods, tank, faucet, membrane and a few odds and ends and it should make you mighty suspicious. If a name brand membrane sells for $30-40 everywhere on planet Earth, a tank is going to run you at least $30 or $40, the faucet is $5. You are already at $85 so that does not leave much for them to work with and supply quality parts and still make a profit. Most of the components are Chinese imports that do not carry any NSF or plumbing code ratings and are of inferior quality. Again good units use name brand housinghs like Amatek and name brand fittings like John Guest along with name brand filters like Matrixx. Its just not the same and has been proven over and over. They made another sale though and thats all that counts to them!

08/07/2008, 08:32 AM	#21
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	Well I understand that you are passionate about quality, and I am too. I just can not afford to spend the money it takes. Your conern about the air gap is a valid one, it is only an issue because of my own lack of experience with RO installs. The last thing I want to do is risk contaminations of any kind. I do have to call you out with a math problem you pose. You say: "You need to replace the prefilter and carbon at 6 month intervals like clockwork, never ever wait a year." followed by " The ones that come with that unit are good for about 1000 total gallons of water before they are spent". I would have to go through 166 gallons every month in order to spend my filters in 6 months according to your numbers. More realistic is probably 60 or 70 gallons a month as a high estimate.

08/07/2008, 08:48 AM	#22
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	You don't change the prefilter and carbon because they are spent, you change them to lessen the likelyhood of bacteria and viruses growing on them. This is another health issue. Now, if you use a 0.2 micron absolute rated prefilter and Chlorine Guzzler carbon which are small enough to trap 99% of viruses and bacteria then and only then you can safely extend your filter runs if you kep track of pressure drop across the filter array and a low level chlorine test kit to monitor chlorine break thru on the carbon. This is a pain for most people so the 6 month method is recommended. You need to understand all the water that eneters the filter goes through the prefilter and carbon, not just the product or "good" water. In a normal system at 4:1 waste ratio that 1000 gallons equates to 800 waste gallons and only 200 total good gallons. Figure that over a 6 month period and its only 33 gallons of good water a month before they are exhausted. Thats another thing the e bay vendors don't tell you. It is actually much less than that when you are using a pressure tank system. When pressure starts to build up in the tank the waste ratio will actually go as high as 20:1 for a good amount of time before the autoshutoff valve finally shuts it off. A permeate pump can help this situation and is recommended with pressurized systems. Like I said it looks and sounds good until you really look into it.

08/07/2008, 09:12 AM	#23
cabrego Registered Member Join Date: Jun 2008 Location: McAllen,TX Posts: 720	I see, you have shared lots of good information. When the time does come to replace prefilters I will definately look into upgrading to the higher quality units that you describe. Thanks!

08/07/2008, 09:59 AM	#24
second_decimal Registered Member Join Date: Apr 2007 Location: houston, tx Posts: 152	you should install a 1lb check valve for the drain. it would at least help prevent backwash etc. and extend the life of the filters / keep things cleaner since you dont have another place to install the drain. another thing to keep in mind, is that when you are ready to replace filters, you shoudl be able to replace them with high quality ones from a non chinese source. they are all universal to my understanding. i like spectrapure myself but there are others that compare. AZ correct me if am wrong here. __________________ "one good thing about music, when it hits you feel no pain"

08/07/2008, 10:05 AM	#25
AZDesertRat Moved On Join Date: Jan 2002 Location: NW Phoenix Posts: 16,621	Check valves may help but they are not approved backflow prevention devices and will not take the place of an air gap. I am also a fan of Spectrapure products, they have untold thousands of hours of lab and real world testing data on all their filters and will not sell anything no matter how small unless it lives up to their standards. They beta test prefilters in some of the worst water conditions in the country before they even bring them to market.