RO/DI filter comparison

[moraym]

The one aspect of aquaria I've never dived into is the RO/DI filters (my old housemate used to have one, so I never needed to).
I've located one for $100 w/ the following:
6 stage 100 GPD Reverse Osmosis RO+DI
4g tank
TFC Reverse Osmosis membrane
GAC polishing post-filter
Stage specs:
1. 5 micron PP sediment filter
2. granular activated carbon filter
3. 1 micron coconut carbon block filter
4. TFC 100 GPD RO Membrane
5. DI (De-Ionized) filter
6. in-line granular activated carbon filter
Stages 1-3 and 5-6 suggested filter replacement = 12 months
Stage 4 suggested filter replacement = 2-3 years
Sell filter replacements for $16 for 1 set (5 filters)
So my question is: I've been in the hobby long enough to know you get what you pay for, but what more do I get by going with a $350 RO/DI system to justify the price hike?

 

[moraym]

Follow-up thoughts:
1. For those of you who run RO/DI, did you purchase a flush kit to flush out the system to conserve membrane duration? Brands?
2. Just noticed in another magazine that lists filter replacements for $50-60 each, so now I'm slightly more curious as to what's up with the unit/filters I found.
THANK YOU ALL.:yes:

 

[acrylic51]

Doesn't sound like a bad unit, but what is the rejection rate on the membrane??? Bigger units of 100gpd usually have a lower rejection rate as compared to a 75 or 50gpd unit. I would ask that question and what manufacture membrane are they using?? Check out AWI their filter prices aren't bad or Custom Aquatics as well for certain filters

 

[acrylic51]

I would also recommend getting a flush kit and depending on the price you could build it cheaper after you see what your actually getting for the money...