Choosing the right RO/DI Unit

[Inconservatory]

There are many brands and styles of RO/DI units out there, to the point where it is overwhelming to the average new reefer. When it comes down to it, what makes one unit different from another? Is a 6-stage Spectrapure better than a 3-stage Coralife?

I see a lot of RO/DI units available on eBay for $100, producing 100 GPD of clean water through a 6-stage process, but I don't see any brands or logos on them. I assume that these are made in China, but does that say anything about the quality? What are the risks of purchasing something like this? Also, are the filter replacements a general fit for multiple models, or would I be pigeon-holed into buying online directly from these sellers?

Thank you.

 

[f2titan]

Wow! I was just looking over the web at these. I want to hear more on this subject. I'm looking for something inexpensive, hooks up to the hose, and can fill a large can for an afternoon water change. I have a 125 gallon tank.

 

[Maxx]

I went with a Typhoon from www.airwaterice.com about 5-6 years ago. I recently noticed a leak from the unit that appeared to be coming from where the bottom of one of the filter canisters connects to the lid. I took the unit apart to see what was causing the leak if it could be fixed. Turns out the lid, (and another) had cracked where the threaded fitting connecting two canisters mated up...

I called Air Water Ice and explained the problem. They immediately shipped me two new lids, no cost. I was told it was under warranty. I explained I'd purchased this unit about 5 years ago...The female customer service rep said it didnt matter, it was covered under warranty.

Got the replacements in the mail two days later...everything works fine...

If I had to do it over again, I would buy the Extreme Typhoon III, (Which wasnt available when I was buying). The fast flush and on board TDS meter are worth it IMO...

Nick

 

[Inconservatory]

I ended up ordering the Typhoon today. I figure that at the very least, the +$80 it was over the shady eBay model was worth the lifetime warranty.

Thanks!

 

[Scooterman]

IMO the important part of RO/DI filters systems is the filters themselves, for the RO, IMO Dow brands are best based on performance charting I've seen. Other than that, the http://thefilterguys.biz/ has great carbon & filter replacement, accessories plus information for most all questions with RO/DI.

 

[Inconservatory]

The Typhoon is here! I'm almost kicking myself for not paying the extra $60 and getting the Typhoon III with the free TDS meter, but I figure this is awesome enough. Since I don't have the TDS meter, I need to go on faith that this product will produce the results I need. Their FAQ says that I should let the unit run for about 3 gallons or an hour upon installation. Will the water be completely fine after this in your personal experience, Maxx?

Also, when the filters start to give out, the flow will diminish. At this point, will the water still be safe but in short supply?


Thank you.

 

[Maxx]

hey sorry I'm just now replying...work's been crazy and the wife is pregnant, so computer time is at a minimum lately...

To answer your question, Yes. after three gallons of wasted output, you should be fine. One thing you might consider doing is either purchasing the hand held TDS meter they offer for $16, (I bought one and it works great) or you can order a digital TDS meter from someone like www.premiumaquatics.com or www.marinedepot.com. They fit into your outflow and will give you a real time TDS reading.

Things to keep in mind:

Your source water will determine how quickly you need to replace filters/membranes. Nasty source water means faster replacements...

RO/Di water is very ionicly "aggresive", meaning that it will rapidly pull stuff from surrounding air sources, so your RO/Di storage container needs to have a lid.

Nick

 

[akunochi]

I just got my Water General RODI unit hooked up and it is very impressive....

 

[treehugger]

puratek makes some great units and the price is pretty reasonable...i install them on all the systems I set up for auto top off.

 

[NaTe R]

i may be off but i would honestly say that WATTS make 99% of all ro units sold by Aquarium Specailty stores. My cousin just sent me over a master catalog (he is a dealer) They ship units to who ever with no labeling and blank boxes for people to sell with there name on them.

I just bought all new filters for my Watts Ro unit from him at a huge discount on what fish stores sell them for

For instance - 1 micron sediment filters $1.00 each
1 micron Carbon Block for $3.35 Each
100 gpd Thinfilm Membrane $26.50 Each

I did see WATTS sells Dow brand membranes as well but they only come in a 75 gpd rating and they quite honestly look like they are manufactured by the same company. maybe Dow has different specs theirs are built to as stated previously.

 

[chris27]

I feel your pain - there are far too many choices out there.

How is your tap water? If the TDS are relatively low your could consider using a DI only filter. The flow through them far surpasses even the best RO/DI unit and there isn't ANY waste water. I filled my 180 Gal in about an hour and a half.

I live in VaBeach, and our tap water is very good, so I just use a large two canister setup from a local company that specializes in home water treatment. The first canister is a carbon filter that gets changed out every 1500 gallons, and the second is a DI cartridge. I monitor TDS, and when it hits 1 I change the DI.

BRS sells this http://www.bulkreefsupply.com/store.../standard-ro-di-systems/dual-di-canister.html which is a dual DI canister, however if you put a carbon cartridge on the first can then a DI cartridge on the second you'd be good to go.

This all is worthless though if you have well water, there are far too many solids in well water and the DI will be exhausted very quickly....

 

[NaTe R]

You can still get good results with well water but it is recomended you add for example a 20" pre - sediment filter that will make your ro/di filters last just as long as your buddys with city water.

Theres alot of options out there for filters as well like .3micron al the way to 20-1 micron filters. (20micron wrap steping down to progressivly to 1 micron so all the stuff doent clog the out side of the filter.)

 

[chris27]

You can still get good results with well water but it is recomended you add for example a 20" pre - sediment filter that will make your ro/di filters last just as long as your buddys with city water.

Theres alot of options out there for filters as well like .3micron al the way to 20-1 micron filters. (20micron wrap steping down to progressivly to 1 micron so all the stuff doent clog the out side of the filter.)

Yea sorry, I was a bit confusing, RO/DI works fine on well water, but DI only will just exhaust too quickly.