Whats the difference between Home and Aquarium RO/DI units?


New member
As the title says, whats the difference? I was looking at one from http://www.purelyh2o.com/, I would like to use the unit for drinking water (since my city water is kinda gross) and to fill/maintain my 125. Is this possible the website doesn't specify the difference.


In Memoriam
Yes you can use the same unit for both. I used to use the small pressure tank that came with my system to store RO water and then had my DI plumbed off of that so I had pressurized water to feed the DI. I later added a second 3.3 gallon pressure tank and finally I just bit the bullet and installed a 14G pressure tank so I can easily get 10+ gallons of either RO or DI water in a hurry. Any of these vendors have home/reef type systems available or can build you something more specific to your needs:
I would contact each of them and see who you like best.


New member
yeah sometimes in this hobby they will charge more for hobby associated things. Like nori or silicone etc.


In Memoriam
Saying that they are the same thing is not a fair statement.
Generally and I say generally as there are always exceptions, a drinking water system uses granular activated carbon instead of solid carbon blocks which are recommended for reef quality systems. In some cases they use a larger micron size and almost always a nominal rated prefilter in place of a higher quality (read: More Expensive) absolute rated smaller micron size filter. They also throw in things like a small post RO carbon filter for taste and odor and count that as a "Stage" of the filtration.
You really have to look closely at what you are buying and read between the lines or you may end up with something that will consume your lunch money budget in replacement DI cartridges or resin. It may also go through membranes faster due to ineffective prefilteration. A granular carbon filter might only adsorb chlorine from 300 gallons of tap water before being exhausted whereas a 0.5 micron Chlorine Guzzler carbon block will conservatively treat 20,000 gallons.
When I say you can use the same filter for both reef and drinking water let me clarify by saying it needs to be a reef quality system to begin with and you jsut use the DI bypass feature for drinking water uses.

Buckeye Hydro

.Registered Member
Residential units also typical have opaque housings rather than clear, don't have a DI stage, and usually use a low flow membrane (e.g., 25 gpd).

Russ @ BFS