Max Water Flow RO, eBay

[Brian Crook]

Here's the link for the one I am considering...

 

http://cgi.ebay.ca/4-stage-Reverse-Osmosis...34.c0.m14.l1262

 

Anyone have any experience with these units? The seller seems reputable and he has all of the filter cartridges available on his eBay store.

 

Any input it welcome! Thanks.

[Scott Riemer]

Looks like only RO.

[Brian Crook]

Oops, yeah. That was a typo.

[Brian Crook]

Well I went ahead and ordered one regardless. Hope it works out!

 

*crosses fingers*

 

(I also ordered a TDS meter so I can check)

[AZDesertRat]

A little steep for RO only.

 

There are also several red flags I see that should get your attention.

For starters it uses a granular activated carbon cartridge. Granular carbons have proven to be very short lived in RO units. Some granular carbons are completely exhausted in as little as 300 total gallons, thats on 60 gallons of RO water and 240 gallons of waste at the normal 4:1 waste ratio which that unit claims to have.

Another is they do not give you a micron rating, gallons of chlorine adsorbed rating or a manufacturers name on the carbon block. This should encourage you to ask the question of the vendor before buying the unit. You want a carbon block in the 1 or less micron range for best chlorine adsorption. I recommend a 0.5 or 0.6 micron KX Matrikx+1 Chlorine Guzzler.

For the RO membrane they state " Dow Filmtec Membrane Material", not that it is a Dow Filmtec. Dow supplies the material to make almost all membranes but that does not make them a Dow Filmtec RO membrane. You might ask whose membrane it is. If its not a name brand like Dow, GE or Applied I might think again.

I see you have already ordered it but you might question the vendor before taking delivery. There really is a difference in filter quality, performance and lifespan.

 

 

 

 

 

Well I went ahead and ordered one regardless. Hope it works out!

 

*crosses fingers*

 

(I also ordered a TDS meter so I can check)

[Brian Crook]

These are the membranes that he claims to use:

 

http://www.dow.com/liquidseps/prod/tw30_181275.htm

 

The carbon filters claim to have a 4000 gallon lifespan and are rated at 5 microns. 1 micron and lower ones are also available to purchase from his store as replacements.

 

I would have purchased a unit from airwaterice.com but they don't ship to Canada. This unit is fairly inexpensive for me because the shipping is minimal and there are no duty fees. Anyways, I hope it works out!

[AZDesertRat]

I feel for you on availability in Canada. We see this often.

If it really is a Dow Filmtec membrane thats great. If its a 75 GPD made by someone else using Dow materials expect a lower GPD production rate, more like 50 GPD at 50 psi vs the Dow at 75 GPD at 50 psi.

At your first filter change at 6 months I would opt for better carbon blocks. There is no way the granular carbon is going to last 3000 gallons no matter what they claim. The block may doe that though. Even then 3000 gallons is only 600 gallons of RO and 2400 gallons of waste, or 100 total gallons of RO per month. The better carbon will stretch that out for you so you don't have to worry about exhausting the carbon and doing damage to the membrane from chlorine getting to it. If you do have chlorinated tap water I would buy a cheap low range chlorine test kit and after a few months use occasionally monitor for chlorine in the finished water just to make sure.

[Brian Crook]

Cool, yeah. We already have chlorine test kits for our spa and pool as well. I'll be sure to check it out with it. I bought a TDS meter from JL aquatics as well so that should give me a good overall idea of how well it's working.

 

If the unit seems to work okay, I will be purchasing some filters to keep as backups and I will definitely purchase the lowest micron ones available.

 

The only thing that confuses me is why is there two carbon block filters on this unit? Is this normal?

 

There's the sediment filter, a GAC carbon filter, a CTO carbon filter, and then the membrane.

 

 

Thanks a lot for the info so far eh! It's very helpful.

 

 

Also, should ALL of the filters before the membrane be 1 micron or lower? Is it okay if they differ? (5 micron sediment and 1 micron carbon?). Thanks!

[AZDesertRat]

There are different trains of thought on RO and RO/DI systems.

One is use a higher micron rated prefilter with progressively finer carbons until you get to the membrane. This sounds reasonable but the drawback is you are depending on the carbon(s) to act as sediment or particulate filters as well as adsorb chlorine and volatile organic chemicals. What happens is the billions of microscopic pores in the carbon get plugged with particulates so they lose their ability to adsorb chlorine and wear out quickly. Two carbons is a carry over from years gone by when carbon quality and product development was not what it is today. There really is no need for two.

The newer thought, after much research and development, is use as fine a prefilter and carbon as possible. The prefilter then protects the carbon, extending its useful life, and the carbon does a better job of protecting the membrane again extending its life too.

Myself personally, after a lot of testing using flowmeters, multiple pressure gauges, inline, benchtop lab grade and handheld TDS meters and low range chlorine test kits, have settled on a 0.2 micron pleated prefilter and a single 0.5 micron Matrikx+1 carbon block. I was pleasantly surprised to find the 0.2 micron prefilter gave me less of a pressure drop than the 0.5 and 1.0 micron prefilters it replaced and lasted much longer due to its pleated sdesign with 10x the surface area to trap particulates. I have yet to exhaust or plug a 0.5 micron carbon block that is preceded by a 0.5 micron or smaller prefilter and thats after about 4 years of testing.

membranes last longer since much of the particulates and sediment never reach the membrane thus don't have a chance to build up or need to be flushed away.

 

If you are considering adding a DI stage down the road you already have most of everything you will need. Take the extra carbon housing and with about 15 minutes plumbing you can turn it into a final DI stage by adding an $8 refillable cartridge and some resin of your choice and moving it to the end of the process. Very easy to do and it works great.

[Brian Crook]

Well the RO unit arrived today. It was packed very well and is a lot larger and heavier than I thought they were. It looks great.

 

The filters are all new and individually wrapped, the bracket is all metal and the tubes all seemed to be connected securely. The membrane is actually made by a company called Lan Shan, and is made using the DOW material like you mentioned. See link here:

 

http://www.lanshan.com.tw/eng/pro_cover_ro.htm

 

Overall I'm actually pretty pleased with the construction of this unit, so I think I am going to give it an honest try. I will definitely be purchasing higher quality filters and eventually a higher quality membrane when it comes time to replace them.

 

The filters for this unit are 2.5" by 10" in size (approximately). Is this a universal size for most filters? Will I easily be able to replace the filters using ones not purchased from this seller?

 

Also, since I have three chambers for filters, if I wanted to make the final one before the membrane a De-ionization stage, would it just be as simple as putting in a DI cartridge?

 

Thanks a lot!

[AZDesertRat]

10" filters are the inductry standard size, you should be able to get replacements that will fit just about anywhere.

Converting the third canister to a DI is not quite that simple but still easy nontheless. Basically what it involves is unscrewing the housings from the top bracket and disconnect the last canister from the other two by unscrewing the nipple connecting them. Insert a 90 degree fittings in what was the center canister so it now leads up to the RO membrane IN like the last canister did previously. So you now have a prefilter, carbon block, RO membrane configuration. Take the loose canister and fasten it to the bracket with the outlets facing front to back not side to side like previously. Plumb the Good water from the RO membrane down to the back of the canister using a quick fitting and have it exit the front again using a quick fitting. You may need to purchase a couple of quick fittings but other than a refillable DI cartridge ($8-$10 empty most places) thats it. You can always dress it up with things like an RO bypass valve so you can use RO only water for drinking and pet watering, ball valves etc. as you find other uses for it.

 

You are really going to like it!