RO unit/deionization filter

[Nebraska_cichlids]

I'm toying with the idea of getting a new RO unit/deionization filter. Based on internet research, my current favorite would be a Maxxima TFC Reverse Osmosis-Deionization Filter. Does anyone have first-hand experience with this or other filters and dares to make a recommendation? What I'm looking for (in that order) are durability, water output and quality, ease of use, price of replacements cartridges, and price of the new unit (and of course compatibility with chlorinated water). Thanks.

Janos

 

[Evan]

I have the Typhoon III Extreme 150 from Air, Water & Ice and I have been very happy with it. Includes built-in TDS and pressure gauges and was very easy to hook up and has been reliable for me.

 

[tjudy]

In my opinion, it is the membrane and the prefilters that are the important parts. The unit itself is pretty much a standard set of hardware. I use SpectraPure, but I am sure other brands have caught up with their quality. In the 80's and 90's they pretty much set the curve (and still do in my opinion). There are only two RO membrane manufacturers in the USA (unless that has changed in the past couple years). So all the unit sellers use one of those. The most important thing is to buy a TESTED membrane with a guaranteed 99% rejection. Cheaper membranes that boast a 95% rejection will dissapoint you.

If you have water with 1000 ppm TDS, then a 95% membrane will only get it down to 50 ppm...

IME, unless you are a reef keeper worried about silicon a deionizer is not needed. Without DI my system takes 250 ppm tap down to 0-1 ppm. Deionizations requres relativley expensive resins that are not (easily) renewable. The cost of the resins is $5 - $10 per 100 - 200 gallons. If you go that route, SpectraPure sells a system that uses a deionization prefilter (between the RO and the deionizer) that extends the life of the resins 3X. The result is a cost of about $2 - $5 per 100-200 gallons. Not to mention the reduced hassle of changing resins.

 

[dfea]

Hi All,

I have the Spectrapure system Ted mentions, its the Maxx Cap RO/DI, mine is a 180 gallon a day. I upgraded to it from my Coralife Pure Flo II and its up for about 2 months now with no problems. I am very pleased with it.

- Dan

 

[Nebraska_cichlids]

Thanks for your quick responses. I looked into your suggestions and now lean towards getting a Spectrapure unit, probably the "MaxPure RO and DI System - 90 gpd"

Dan, do you see a reason to go with the Maxx Cap rather than the MaxPure? I keep about 25 tanks, all the way from 5G to 125G, and I use RO/DI water only in some of them (primarily the ones 40G and less that I use for breeding).

Janos

 

[tjudy]

I have the MaxCap RO/DI system and installed a closable bypass to the DI. That way I do not have use DI if I do not want it. After having it for about 2 years I think I used it once.

 

[dfea]

Hi Janos,

Short answer is yes, but keep in mind my nickname is overkill.

I had the exact same question when I was looking at upgrading. So I called Spectrapure and they told me that the MaxCap was their latest technology and provides not only purer water but longer lasting Deionization cartridge life which in the long run saves money. From what I understand the MaxCap RO/DI system comes with a bit finer pre-filtration (sediment and carbon block) but more importantly it uses their SpectraSelect RO membrane while the the MaxPure RO/DI is packaged with their standard membrane. This speaks to the point of Ted's earlier post on membrane quality. The SpectraSelect membrane is guaranteed 98% rejection while their standard membrane is 96%.

Now with all that said, I went the RO/DI route as I has aspirations of setting up a Reef tank (nixed now as I am hooked on Westies) and Ted is also correct in that you would most likely do just as well with a RO only system. The advantage there is that you can either get the same production volume for less money or even better you can get much higher volume for the same money.

My advice is buy as much production as you can afford.

Hope my babbling helped - Dan