RO/DI - What's the difference between 4 stage and 5 stage units?

[DC_40gallon]

Other than the obvious, you have an additional filter.

I like Buckeye Field Supply units and they are 4 stage units but they are cheaper.

I like thefilterguys.biz units and they are 5 stage units but they are higher.

Why go for one vs the other if the whole point for every RO/DI unit is to get final output 0 TDS?

[jason2459]

One more container to put some type of media in. I've seen 5 stage either have two carbon blocks for those area's that have really high chlorine or chloramine in the water or I've seen two stages of DI for those that like to rotate the DI changing process.

examples:
4 stage
sediment > carbon > ro > di

5 stage
sediment > carbon > carbon > ro > di
or
sediment > carbon > ro > di > di

I've also seen
sediment > ultra fine sediment > carbon > ro > di

I'd try and find out what's in your water then talk to one of the people that you listed to see what would work best for you.

[bsagecko]

buckeye field supply has an overall solid unit

thefilterguys has a decent unit but penny to penny buckeye is usually better in terms of price

The basic desirement for an Ro/DI system is that it has 3 prefilters...then the ro membrane...then a vertical DI system.

You do not want a horizontal di system...

the prefilters are usually arranged in either a 2x sediment 1x carbon block or 1x sediment 2x carbon block depending on your individual water needs...

Spectrapure actually makes the best system for hobbyists but it is a lil higher than most...

I have an Ro/DI system from thefilterguys...and it works well...I did change the prefilters though because the micron ratings on the filters were not low enough for my liking...

I would go with the buckeyefield supply unit as long as the DI is vertical...if you want economical

thefilterguys....have a good product and are nice ppl with great customer service

Spectrapure is simply the best

[DC_40gallon]

thefilterguys has a decent unit but penny to penny buckeye is usually better in terms of price

The basic desirement for an Ro/DI system is that it has 3 prefilters...then the ro membrane...then a vertical DI system.

With that being said, I cannot find a unit with Buckeye Field Supply that is a 5 stage unit. Unless I simply and completely overlooked it. I would prefer a 5 stage just to have that additional filter to push through.

[Randy Holmes-Farley]

A setup with two DI units allows better use of the DI cartridges before discarding them. The first can be run until the TDS rises to maybe half the TDS of the incoming water, then discard it and replace it. All the while having 0 ppm TDS output.

With a single DI, you need to swap out the DI and replace it as soon as the TDS begins to rise above 0 ppm TDS.

This may also help:

Reverse Osmosis/Deionization Systems to Purify Tap Water for Reef Aquaria
http://reefkeeping.com/issues/2005-05/rhf/index.htm

[Playa-1]

I agree with Jason, It just depends on the filter as to what the difference is. It depends on your water quality going into the filter and what your trying to accomplish as to which filter is best for you. I would suggest that you do a little research to find out if you water is being treated with Chloramine at any time during the year or if they just use Chlorine year round. That may effect your decision as to which filter you should get. If somebody were on well water they would likely have a completely different set of issues to deal with then somebody in a big city.

[Jaycen B.]

You could add extre housings to any system if you feel the need. Buckeye offer some good features like flush valve and DI bypass so when you flush your RO it does not run through your DI they also come with a TDS meter on the premium series.

[DC_40gallon]

Sounds like the reef+1 from thefilterguys.biz is the way to go since it's $20 more but has the extra filter stage and it has everything that buckeye field supply has.

[moze229]

Originally Posted by DC_40gallon

RO/DI - What's the difference between 4 stage and 5 stage units?

1 unit.

Sorry, couldn't resist

Matt

[Playa-1]

Originally Posted by DC_40gallon

Sounds like the reef+1 from thefilterguys.biz is the way to go since it's $20 more but has the extra filter stage and it has everything that buckeye field supply has.

I think you would be happy with that filtration system.

[Henry Bowman]

Difference between 4 stage and 5 stage......1 stage.

Sorry I couldnt help it !

There are some good answers above. If your tap water is high in TDS, you will end up needing the larger unit. AND.... I didnt even purchase my unit from thefilterguys but they have my business now for all my replacement cartridges. VERY nice folks, willing to help AND they are reefkeepers themselves.

[PRDubois]

Extra stage of carbon

[akcastueras]

I have the filter guyz 5-stage, tds meter says 398 coming in 2 going out. I'd say that's decent. I do get like 1g ro/di for every 4-5g waste, wonder if that's normal...

[DC_40gallon]

I've heard that is normal, 4:1 ratio on waste water to pure water is about right.

You can add a additional membrane on thefilterguys reef+1 for $77 I believe. looks real simple to add too and it sends the waste water through the 2nd membrane and drops it to 3:1 or less.

That kit might be on melevsreef.com, either way check both places if your interested. The kit just literally snaps another membrane on top of the existing.

[Buckeye Hydro]

I wouldn't fixate too much on the number of stages. Look at what each stage in a system does, and add more stages only if needed. So if you have a typical feeedwater w/o chloramines, I'd ask why is it you want an extra carbon stage?

If you have heavy sediment loads you might want an extra sediment filter in front of the membrane.

Don't fall into the trap of thinking "more stages is better." If you do, try some of those 6 or 7 stage systems on ebay!

Russ

[DC_40gallon]

Ah the great Russ -

Thank you for the insight, I knew you were lurky around somewhere.

[gmr7494]

For $150, you could get a 4-stage Spectrapure ProPlus 90GPD. I got mine yesterday. Works great and even has a TDS meter.

[loosecannon]

I did not have a filter system for first two years. Then I find out the lake water that my son and I were not a loud to swim in because it was to piloted, was going to be my Townes new drinking water! Now I have a 3 stage going in to a 5 stage then in to a storage tank. The tank feeds water to the sink for drinking and cooking. I have a valve I turn on the runs the tank water thou a dual D/I with a tds meter. The water goes in at 6 to 10 tds and comes out at 0. I run the gray water from my first filter to the second one and use a booster pump so I wast as little water as possible.