Reverse Omosis Qaulity Debate - Ebay vs Fish Store/Site

[mnestroy]

Okay I'm still trying to get a good solid understanding of reverse osmois systems.

The debate is simple... are the systems you find on ebay for a 1/3rd of the price just as good as the ones you find on a aquarium store/site?

I'm looking to purchase one, and I can get a 6stage on ebay for around 100bux.... and for the same price a 2 or 3 stage on most aquarium sites/stores...

Has anyone had good luck with the 6stage filters from Ebay? or does name brand really matter?

Arent the actual filters the same?

[mitlik1]

I am not sure. Here is a link to a cheaper water filtration system.
http://cgi.ebay.com/REVERSE-OSMOSIS-...QQcmdZViewItem
This one removes up to 96% of TDS. Maybe that is the difference. I would be interested in thoughts also.

[Paintbug]

i bought my RO/DI from Aquasafesystems on Ebay. i have had it for over a year now, and im just now seeing 1ppm on the TDS meter. i paid $117 shipped, and couldnt be happier!! mine is just like this one http://cgi.ebay.com/AQUA-SAFE-AQUARI...QQcmdZViewItem he will email you the instructions, they are very detailed. i will add that they are in Canada so it may take a day or extra on shipping. another guy on Ebay lots of people here use is Filterdirect.

[Infern0]

Here's a link to a thread I started on size...give a lot of good links and advice in purchase.

http://www.reefcentral.com/forums/sh...hreadid=848217

[Vincerama2]

I use the Aquasafe RO/DI unit as well. I've had it for 3 years and, due to laziness, just replaced the pre-filters. The first filter stage looked like it was covered in MUD!

Very good unit. RO Units are basically all the same. Aquasafe, though it had $30 shipping to CA, had the best price for what I got. Make sure you get a holding tank!

V

[AZDesertRat]

6 stages don't mean a hoot when it comes to a reef system. The cheaper ones use a GAC filter which is not desired as it contains fines and dust that can clog and slow down a membrane. They also use a GAC post filter that is only used for drinking water or ice makers and again of no use in a reef RO/DI, in fact its detrimental. Most use less desireable membranes some even use nano filters and not true RO membranes. Most use POS hollow tubes that hold 6 oz of DI and call it a DI filter.
Yes there is a difference. I suppose there are some happy ebay customers out there but I would bet you a dollar to a donut they would be much happier with a better unit. Most ,, if not all have never seen a good RO/DI or tested the units side by side and have nothing to compare them to. Unless you have very close to pristine water conditions to begin with, it is not worth the few dollars diference to skimp on quality. You will eventually invest thusands of dollars in your reef and water is the most important part of it so why not provide he best you can.
You will have invested more in upgrades by the time you are done than if you had just bought the good one to begin with.

[serpentman]

I can second AZDesertrat's comments. I for one, bought the cheap ebay unit. With modification, I am getting ok (not optimal performance). I had to use almost a whole roll of teflon tape to get the RO membrane to seal into its housing. Furthermore, the DI unit only came partially filled. Because of this, water is able to bypass the DI resin in the chamber causing me to get DI readings around 5 on a unit that is only 1 month old. I will have to either replace the DI unit or get more resin.

[Vincerama2]

I get 0 TDS from my RO/DI unit. The GAC is between the RO and the drinking water tap. The DI unit comes straight off the RO unit as well.

Actually, right after the RO unit, I have T'ed the line to the reservoir tank, the GAC/Faucet, and the DI/valve.

So when I drink water, it's RO then filtered. When I want RO/DI water, it does not pass the extra GAC.

I've had no water quality problems with the AquaSafe Canada unit in the 3 years I've had it, and like I said, I use a TDS meter and it shows the RO and the DI units to work just fine.

This is just my own experience, I'm not a water expert.

There are many cheap eBay units, just as there are many expensive units. I can only speak for the unit I bought 3 years ago.

V

[AZDesertRat]

You should get 0 TDS after the DI on any unit sold or you are getting stung. The real story though is what is the membrane doing? What is your tap water TDS and RO only TDS?
Any unit should give you 0 TDS after DI but as said time and again, it wil only make 0 TDS for a given amount of water and thats where the better units shine as the membrane is more efficient so the DI doesn't have to work as hard and even then there is much more DI in the housing and it flows through the resin much more efficiently thereby fully utilizing all the resin to its full capacity.
Everyone, tell the entire story when you are saying 0 TDS. Also include raw water and RO only data as we are talking about a system here and not just DI resin. I can get 0 TDS with a $20 Tap Water filter all by itself, although not for long.
Example
Raw water 630 TDS
RO only 11 TDS
RO/DI 0 TDS
These readings were taken yesterday. Thats with a 2 year old 75 GPD Dow Filmtec membrane and a standard 10" vertical style DI filter. No flush valve and a 6:1 waste ratio.

[sidd129]

Spending money sucks, but you should wait and save up a little more to get a good unit.
go with either airwaterice or the filterguys.biz

[Steven Pro]

As AZDesertRat has said, any RO/DI unit can give you 0 TDS product water. The question is, what is it going to cost you long-term for that product water in comparison to other units.

Here is an example. Tapwater has a TDS of 200. A low cost RO/DI unit removes 90% via the RO membrane to produce water with a TDS of 20, which the DI cartridge resin removes the rest of bringing the final water to 0. A better quality RO/DI has a 98% rejection membrane and produces water with a TDS of only 4 post-RO membrane, which again the DI removes the rest producing 0 TDS water. But, the "low-cost" RO/DI will go through five times the DI resin as the unit that costs more initially. So, the "low-cost" unit will end up costing more than the better unit. It is just a matter of time.

[Paintbug]

i will add that my water isnt bad here by no means. i usually get 70-80 ppm on the TDS meter. but i have been using my Aquasafesystems unit for over a year and i havent changed any of the filters, or DI resin. i am just now seeing 1ppm TDS. theres no way anyone will ever convince me i made a bad purchase!

[clord]

Just buy the one on ebay and save some money if you don't have a lot. You are not going to notice any difference as long as your tds is low. Theres a guy I know that has a perfect running a reef tank for years using tap water. If your going to be keeping softies/lps you will be fine sps maybe different but I dont know much about it.

[sidd129]

I'm sure someone can explain a lot better than me why a system running for one year is headed towards doom. Ok, maybe not doom but....

I'm not trying to flame. I'm just in a goofy mood from working midnights.

[RicksReefs]

I have the same 6 stage aquasafe canada.

385 from the well, 6 after RO, 0 after DI.

almost all membranes (around 95%) are made by DOW/filmtec, regardless of RO/DI maker (mine is).

sorry, I can't see justifying spending $400 for essentially the same thing as my $65 unit that I've had for 3 years with no problems.

some people just need to justify spending to much on things.

[AZDesertRat]

Rick,
who is spending $400 on a RO/DI ? None that I have seen are half that number. Also unless you did something special you unit does not have a Dow Filmtec RO membrane in it, you better lok at it again. AquaSafe uses Applied Membranes 100 GPDs in their units which is not a Dow. Don't spread inaccurate information either on pricing or materials, thats not productive.
A Dow is designed to operate efficiently at 50 psi. An Applied is designed to operate at 60+ psi so there is a difference and in some cases it can be substantial.
A good RO/DI will run you between $149 and $199 and those are accurate numbers. A good RO/DI wil include a Dow Filmtec 75 GPD true RO membrane and that is an accurate statement. A good unit will also include a standard size 10" vertical canister with a refillable cartridge containing 24 oz of nuclear grade resin not a horizontal hollow tube containing 6 to 16 oz, thats another accurate statement.
You get what you pay for with RO/DI and cheap is not where its at.

[Shoestring Reefer]

Originally posted by AZDesertRat
6Most use less desireable membranes some even use nano filters and not true RO membranes.

From what I've read, that's true of any single membrane rated for 90-110 gpd or more, not just the Eaby ones.

But, you've got to consider just how clean the water really needs to be. After all, some people (not me) are lucky enough to be able to use tap water it their reef tanks, and I imagine a nano filter (vs a true RO) will get my water cleaner than what comes out of their tap.

[Vincerama2]

For my 3 year old Aquasafe, which I just recently (2 weeks) changed the prefilters on;
TDS numbers
Tap = 51
RO (and post RO GAC) = 7
DI (right off RO, not through GAC) = 0

The RO membrane is about 3 years old, the DI cartride, which is a small horizontal one is about 2 years old. I use my unit to top off my 80g system (58 main and around 20 sump) and to drink from (the RO+GAC part, not the DI).

The water seems fine to me. I'm very happy with my AquaSafe unit, I don't really care what RO membrane manufacturer it is. When it dies I'll buy another membrane.

For my money, I think it was worth it. Even if the filters and the RO and DI things die, I still have the basic unit (the cannisters, the tank, the faucet, the auto-shut off, the flush valve) that I can re-fill with better filters if I want to. Seriously, it's a bunch of plastic containers with tubing. If it's full of crappy filters etc, they can be replaced when they fail, so far mine have been holding up fine.

V

[RicksReefs]

Originally posted by AZDesertRat
[B]Rick,
who is spending $400 on a RO/DI ? None that I have seen are half that number.

this was the first sponsor i found in 30 seconds...

http://www.premiumaquatics.com/Merch..._Code=SP5stage

Also unless you did something special you unit does not have a Dow Filmtec RO membrane in it, you better lok at it again.

not to cope an attitude but, I don't need to. I unwrapped it and installed it. it's a DOW.

you can spead all the mythinformation you like, bottom line is O TDS...

have a nice day.

[Steven Pro]

Originally posted by Vincerama2
For my 3 year old Aquasafe, which I just recently (2 weeks) changed the prefilters on;
TDS numbers
Tap = 51
RO (and post RO GAC) = 7

By my calculations, your RO currently has a rejection rate of only 86%.

[Vincerama2]

This brings up another good issue... RO units waste ALOT of water. Not just crappy water, but water that has gone through all your pre-filters, so it's actually better than tap water! And even if whatever is rejected by the RO membrane is in slightly higher concentrations in the "waste water", it's still way better water than your tap water.

Some people use DI only, and use rechargeable resins of both types (cation and anion) in those big 10 inch filter things. (Of course you should still use prefilters!). Just a thought.

And yes, I know at some point I'll have to replace my RO membrane, or risk wasting alot more water.

V

[lvmartian]

ok...say you bought a Typhoon III, would it be plausable to tell the ol' lady she could drink the water? Eases up the purse strings if ya know what I mean...

[AZDesertRat]

You betcha. They have a DIbypass valve so you can use RO for drinking and cooking and whatever and RO/DI for the tanks. They are designed that way.

[BetiumInside]

AZDesertRat,

I like your arguments and I am looking to buy one, can you send me the link of the site that would have the one your are talking about?

Thanks,

Betium

[sidd129]

What does this $400 ro/di have over the $199 ro/di? I'm just curious.