davebell24
New member
I'm looking to buy a ro/di system..
Spectra pure or the Kent Marine system
Or is there a better one,
Please No Ebay Crap!
Spectra pure or the Kent Marine system
Or is there a better one,
Please No Ebay Crap!
Which ro/di system is better
- Thread starter davebell24
- Start date
Mangas8282
New member
Ummm, excuse me, ebay crap??? I bought my RODI off ebay, and I think half the other people on this board probably got there ROs off there too. If you want to go spend $350+ for a Kent or other RO unit, that is your perogative. I picked up a 6-stage from filterdirect for $109 shipped to my door and it works great. I had the output water tested and it is perfect, escpecially since we have horrible water in Gainesville.
GoldStripe
New member
The cheap ones on eBay work fine. Been using one for about 2 months now for top off and water changes. From what I hear TDS readings are right around 0. That's all we care about....
Ironsheikh
New member
I got the 110 g a day from ebay as well-- didnt go for the drink tank and faucet version-- so I spent $100 about. just hook it up and put what you need. I have deionization and it works fine for me. I use it for drinking water as well -- I can really see a difference just by the color of my tea I drink. I use it for my marine tank and my betta water ... (I have 6 right now and they make a bubble nest by the next morning I change their water). Marine aquariums can nickle and dime you to death--save money when you can -- but if you have to have the name brand --go pay $200 extra and you don't even get the Deionization with it.
aquaman67
Active member
The E bay systems use a membrane that is only 90 % efficient.
Other systems like Kent and Specta Pure use membranes that are 98 % efficient.
http://www.dow.com/liquidseps/prod/home_ele.htm (look at the bottom - 100 GPD membrane)
What is the difference?
The water that comes out is indeed 0 TDS because of the DI. You can put tap water into a DI and it will come out zero.
http://petsolutions.com/product.asp_Q_pn_E_17101175_A_Tap+Water+Filter_E_
The difference between the E Bay systems and the others is that while cheaper at first, the will use up DI cartridges much faster.
Don't believe me? Measure your tap water TDS. Take the line loose that goes into the DI from the RO membrane. Take another TDS reading there. If your tap is 200 TDS, your RO only will be around 20. With the name brand RO units that same tap water will be 4.
All the RO is is a mechanical filter for the DI. The RO rejects molecules based on size alone. The more you remove by RO the less you have to remove by DI.
People think because they paid a few dollars less on E Bay and their water comes out 0 TDS they think they got a good deal.
While crap isn't a word I'd use to describe the E Bay units, I myself use a Kent 60 GPD Hi-S. My membrane will be three years old in Oct and is still 97 % efficient. Your E bay unit couldn't do that when it was new.
Do any of the E Bay units list the efficiency of their RO membrane?
Kent does.
If your E Bay unit does please post it here, it'd like to see it.
Other systems like Kent and Specta Pure use membranes that are 98 % efficient.
http://www.dow.com/liquidseps/prod/home_ele.htm (look at the bottom - 100 GPD membrane)
What is the difference?
The water that comes out is indeed 0 TDS because of the DI. You can put tap water into a DI and it will come out zero.
http://petsolutions.com/product.asp_Q_pn_E_17101175_A_Tap+Water+Filter_E_
The difference between the E Bay systems and the others is that while cheaper at first, the will use up DI cartridges much faster.
Don't believe me? Measure your tap water TDS. Take the line loose that goes into the DI from the RO membrane. Take another TDS reading there. If your tap is 200 TDS, your RO only will be around 20. With the name brand RO units that same tap water will be 4.
All the RO is is a mechanical filter for the DI. The RO rejects molecules based on size alone. The more you remove by RO the less you have to remove by DI.
People think because they paid a few dollars less on E Bay and their water comes out 0 TDS they think they got a good deal.
While crap isn't a word I'd use to describe the E Bay units, I myself use a Kent 60 GPD Hi-S. My membrane will be three years old in Oct and is still 97 % efficient. Your E bay unit couldn't do that when it was new.
Do any of the E Bay units list the efficiency of their RO membrane?
Kent does.
If your E Bay unit does please post it here, it'd like to see it.
Last edited:
aquaman67
Active member
I found one myself. Here's the Filter Direct 110 GPD Aquarium model.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20756&item=4364811737&tc=photo
I see now how they get around listing the efficiency of the membrane. It's there, you just have to do the math.
About in the middle of the page they give an example of tap water at 300 TDS. After RO they say it will be "around 20". That's only about 93 % efficient. (93 % would be 21 TDS)
With a 98 % efficient Kent unit that same tap water would come out of the RO at 6 TDS.
When my Kent membrane gets to 93 % efficient, I'd replace it.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20756&item=4364811737&tc=photo
I see now how they get around listing the efficiency of the membrane. It's there, you just have to do the math.
About in the middle of the page they give an example of tap water at 300 TDS. After RO they say it will be "around 20". That's only about 93 % efficient. (93 % would be 21 TDS)
With a 98 % efficient Kent unit that same tap water would come out of the RO at 6 TDS.
When my Kent membrane gets to 93 % efficient, I'd replace it.
vermonter310
New member
aquaman67 said:
While I agree with all your points, When I replace my Membrane on my Aquasafe unit I'll put in a true RO one for $60-$70 and replace my DI cartridge for $14. Total investment of less than $200 over the course of 2-3 years. Can your Kent do that.
With the ebay units, all you have to do is ask for a "true membrane" even though what is in the unit is a real ro membrane anyway. Just ask for a 75 gal per day membrane and they will switch it for free (it is 98% efficient). Then you still save money and you have just as good a membrane as the kent unit. Only 2 companies make ro membranes.
aquaman67
Active member
vermonter310 said:While I agree with all your points, When I replace my Membrane on my Aquasafe unit I'll put in a true RO one for $60-$70 and replace my DI cartridge for $14. Total investment of less than $200 over the course of 2-3 years. Can your Kent do that.
Is $219 close enough?
http://www.marinedepot.com/md_viewItem.asp?idproduct=KM1433
Plus if you buy from MD they give you 15 % off replacement cartridges.
Ironsheikh
New member
big dave, trust your gut -- my set up works for me/ the other guy's works for him--a damn brita is better than the water I had before. Lol
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