RO/DI, few questions?

[BL1]

It's been a week and I've already gone through 40 g
allons of store bought water! So, today or tomorrow I'll be buying an RO/DI unit. I'm trying to find a unit between $150-200 but, there are so many options out there. I'm not too worried about gpd since I don't use more than 10g a day anyway. But, I'm hoping someone can explain what the stage numbers mean .... is 3 stage ok for an aquarium or should I go for a 5-6 stage system?

Here a few few I've been looking at:
AQUA REEF RO DI REVERSE OSMOSIS PUR WATER FILTER SYSTEM - eBay (item 350324650649 end time Mar-16-10 16:00:31 PDT)
75 GPD RO/DI 4 Stage Standard System - English
75 GPD RO/DI 4 Stage Economy System - English
Aquarium Water Quality: Pure-Flo II RO Units

 

[Hiker4twenty]

The first system you have listed by Filter Direct is perfect. I actually installed that very same unit last night and it works great. Instructions are very good and it's very easy to install and use.

 

[Bifferwine]

You should go for at least 5 stages (mine is a 5 stage unit).

 

[VAreef]

As for the filter direct model I have that one and the stages are:
1st stage is a sediment filter, 2nd and 3rd are carbon filters, 4th stage is an RO membrane, 5th and 6th stages are DI resin chambers.

 

[BL1]

Hiker & VA, thanks for your suggestions ... I just ordered mine from Filter Direct, and I'll be looking forward to not having to go to the store and pay to lug water back home.
Thanks Again!

 

[Hiker4twenty]

Any time and best of luck with the new unit!

 

[Buckeye Field Supply]

Unless you have unusual tap water, such as water that contains chloramines, or has high sediment loads, there is no reason for more than 2 prefilters (the filters that come before the RO membrane).

With typical tap water, we recommend a 1 micron sediment filter followed by a 0.5 micron carbon block (NOT GAC!).

Those prefilters should be followed by a RO membrane and a full size, vertical, refillable DI resin cartridge (for a total of 4 stages). Add more stages only to address specific issues.

Russ