Suggest an RO/DI

[fsn77]

The DI step is not the wasteful step, it is the RO membrane where the waste occurs (if you're talking about wasteful in terms of water being wasted).

I have the unit sold on MelevsReef.com. I've been using it for almost 2 years now and it's worked exactly as it should. It was a bit cheaper 2 years ago when I bought it, but it's still a nice unit.

This unit is also popular with some of the reefkeepers in our area:
$160.00 - OCEAN WAVE+ FIVE STAGE 75 GPD RO/DI
http://www.thefilterguys.biz/ro_di_systems.htm

Personally, I wouldn't advise buying a RO or RO/DI unit with a rating of < 75 gpd. Production rates are based on ideal operating conditions (water pressure and temperature), which many of us do not consistantly meet within our homes. Even if those conditions are met, it still takes roughly an hour to make 3 gallons of product water with a 75 gpd unit. This time of year, even living in the south, actual production is about half of the 100 gpd rating on our RO/DI unit. It's only during the warmer months that we're able to get close to actually making 100 gpd.

 

[kcress]

I'm lucky cuz my domestic pressure is ~100psi.

Not sure who said wasteful? I run months between waater changes and make up ~2 gallons a day from scanky city water using just RO. I am happy to not have to worry about a DI column. I can get a few years out of my filter caisters and the membrane. With a DI added.. Probably not even a year.

I totally agree with bigger is better though. I had a 25g/day. I lived with it. Having a pressure tank meant that I always had several gallons on tap. But making batch was a multiday waiting game. I just upgraded to a 90g/day certified membrane and now I get about 120g/day (because of the insane water pressure) and making a 32g garbage can full of RO only takes a few hours. Much nicer.

 

[SuperScro]

My tank is not very large, and I am not sure if the GDP makes a difference here or not. I don't care how long it takes to make the water, I just want it to be good for my tank.

By wastefull i meant the water being wasted, sorry for not being clear.

 

[kcress]

Oh yeah.. That is a very obnoxious aspect of RO. I plumbed mine to a small sink fixture that runs whenever product is being made. It drives people mad.. "You're wasting water!" gawh!! So often there's a pail sitting under it.

 

[Grins]

It doesn't have to be wasted though. It can be used to do the laundry, water the yard, etc.

 

[nycsicktank]

or you can save it up on a bucket for fw water change for later on

 

[Grins]

Um, why do that?

edited...I thought you meant a FW top off for a SW tank. Did you mean if you have a FW tank too?

 

[nycsicktank]

yea. i mean the waste water from ro, you can use it for fw.

 

[rsw686]

I've gone through two different RO/DI systems. It's better to just buy the one you want upfront than to buy two. The first one was an RO only unit from Corralife. It was putting out traceable amounts of ammonia so I bought the DI addon. That solved the problem, however it was only a 50GPD, which was annoying, and had no TDS meter, auto-shut off, etc.

The money I sold it for I was able to buy a new RO/DI unit from The Filter Guys with everything on it. The end cost was less than adding that items to my existing unit.

The TDS meter is highly valuable. It lets you know if your RO membrane is functioning properly and when you need to change out the DI resin. I spent just over $200 for everything shipped.

 

[SuperScro]

I"m slightly confused. How does the GPD amount matter?