Are all RO units equal?

[porter]

Hello all. Just getting back into the hobby. I moved to the city so now believe I need to get a RO unit. I've found a few new units that say they are for drinking water at a fairly good price. My question is are all RO units equal? Thanks for the help. Not sure if I'm allowed to post live links but I've found one on flebay that produced 100GPD for around $100. sound right?

 

[scsinet]

It's far to say that all RO cartridges are rated equal. A "4 stage" unit from one brand/vendor is going to be basically the same as a "4 stage" unit from another.
However, the stages matter, and RO units for drinking water lack a DI (Deionizing) stage, which while it is not required for aquariums is really, really a nice to have, because it removes phosphates and such from the water.
You can easily add a DI stage, individual canisters and DI resin cartridges are sold separately and are very easily plumbed in, but you can save more money by buying the correct unit outright. I recently upgraded my Kent 4 stage to a 5 stage from a/w/i for $150, of course including the DI stage. That's one of the better deals out think, and it'll be a better deal than buying a separate DI stage for your system.

 

[bla403]

I have a 4 stage with pump & tds meter. I like it alot better than my older cheaper unit which just hooked up to the sink. I get much better water out of this one since it uses the nicer cartridges in the canisters. The pump is great since I get water a lot faster with less waste.

 

[porter]

Originally Posted by SCSInet
http:///forum/post/3115690
It's far to say that all RO cartridges are rated equal. A "4 stage" unit from one brand/vendor is going to be basically the same as a "4 stage" unit from another.
Ok, so regardless if I were to get an RO unit from a hardware store (not selling for aquatic use) or a LFS (is selling for aquatic use), they would both yield the same results correct? Assuming of course they were both RO only and the same "stage".
Thanks guys.

 

[scsinet]

Yes, but as I said earlier, units not sold for aquarium use generally lack the deionizing stage, which is significant in this application.
RO units without DI are not going to yield nearly the water quality of those with.

 

[porter]

Thanks, that answers my question. I appreciate your help.

 

[tank a holic]

I assume the units you're looking at are rated at the same GPD??
also, your final stage may be different as far as how big in microns it will let things pass, some have a 3 micron filter and some have a 1 micron filter, some are probubly even more

 

[kearj74]

what if you have well water do you need an ro di unit? i wanted to buy an ro unit for our drinking water and thought i could use this for my aquarium water too but if i get one with ro and di is that ok for drinking water too?

 

[tank a holic]

ro water is ok to drink, thats what bottled water is
di water on the other hand is not supposed to be drank

 

[bang guy]

There is also a "High-S" RO membrane. A regular membrane will remove 90 - 94% of contaminants, a High-S will remove 98 - 99%, Silicates being the major difference between the two.

 

[jetskiking]

It is very important to use DI which you will not get in a drinking water unit. You will not get 0 TDS out of just a straight RO unit. ussually it gets it to around 20ppm. I change cartridges at over 5ppm. The deionization strips the rest of the contaminents out which is also why its not good to drink. The water we drink contains minerals such as calcium that keep our teeth in our mouth. If you also want to use it for drinking water put a T and a valve just after the RO but before the DI.
As far as well water goes, I would not use it because it might contain heavy metals and such. I also don't use tap either.

 

[bang guy]

Originally Posted by kearj74
http:///forum/post/3123818
what if you have well water do you need an ro di unit? i wanted to buy an ro unit for our drinking water and thought i could use this for my aquarium water too but if i get one with ro and di is that ok for drinking water too?
On my system the RO feeds a storage tank for drinking water and another line goes through the DI to the aquarium. Best of both worlds.