RO/DI Filter Help

[Tony]

Hey all,

I got this unit used 5-6 years ago for making reef tank water.

I haven't used it in some time and am pretty certain that I need to replace the cartridges in it. My issue is that I have no idea what each section is and what it does. I don't believe that all of the pieces are even necessary for my application.

I plan on using it to make water for my 150 eartheater tank as well as for the plecos and West Africans. With this in mind, I'd like to be making a lot of water (it's currently very slow - probably because of the old cartridges, membrane and stuff). I know that it's all about tradeoffs - water with lower TDS takes longer to make. Pretty sure that for my application, my guys would be fine with higher TDS if it meant making water twice as fast.

So does anyone have any idea what all the parts on this thing do? Any recommendations on a place with good prices for getting the cartridges and membrane?

Thanks in advance.

 

[Nathan]

throw out the top 2 filters.
Do you know how many gpd its set up for? You need a new membraine and maybe a new restrict0r if you want to upsize.
The bottom 3 can be configured how ever you want, I have mine set up with a sediment 1st, and then 2 carbons.
https://www.wateranywhere.com has good prices

 

[Tony]

throw out the top 2 filters.
Do you know how many gpd its set up for? You need a new membraine and maybe a new restrict0r if you want to upsize.
The bottom 3 can be configured how ever you want, I have mine set up with a sediment 1st, and then 2 carbons.
https://www.wateranywhere.com has good prices

Thanks Nathan. Not sure what the intended flow rate of the unit is. Does the membrane typically control the flow rate of the unit?

Great website with pretty solid prices! They have all sorts of cool, stuff there.

Thanks again.

 

[mscichlid]

http://www.aquasafecanada.com/store...embranes-beads/aquarium-ro-filters-case-of-18

 

[Nathan]

Thanks Nathan. Not sure what the intended flow rate of the unit is. Does the membrane typically control the flow rate of the unit?

Great website with pretty solid prices! They have all sorts of cool, stuff there.

Thanks again.

Somewhat, it looks like you have a valve instead of a set flow restrictor, so you should be able to use any sized membraine. you'll just have to set the restrictor manually (its the valve on the wast water line)

 

[Tony]

So is the DI resin section of filtration generally considered overkill/wasted money/flowrate for freshwater setups?

 

[Tony]

http://www.aquasafecanada.com/store...embranes-beads/aquarium-ro-filters-case-of-18

Sweet deal!

 

[Avatar]

Your municipality probably uses chloramine

Takes different cartridge set-up to neutralize than what is used for chlorine.

One can basically double outflow by boosting input pressure, not my field but I almost spent $100 on a pump to do this with my own system, might be worth looking into...

 

[blkmjk]

Umm so you dont actually need RO. A Sedimate,Softener and Carbon filter will suffice your needs.

 

[blkmjk]

So is the DI resin section of filtration generally considered overkill/wasted money/flowrate for freshwater setups?

Ok so to clarify a little bit without losing everyone RODI water is ReverseOsmosisDeIonized water. In short the membrane is such a restriction to the flow of water that only pure H2O can pass through. That is RO water this is also why a pump is required on large capacity systems. A softener is the DI the way that this portion works is you have a resin that has a affinity for iron ,calicum, and other disolved solids. It completes this task through electron exchange and replace ment with sodium ions or Brine as it is called on a typical softener.
So a alternitive to RO is Carbon filtered water. No regenertaive cost IE membranes need to be replaced every 6 months or so. And are costly in most cases.

Hopefully this clears it up a bit for everyone interested in a RODI system. I can go into greater details if needed.

Drew

 

[dlfn1]

so drew, u are saying u can just run water through carbon, like that used in HOB filters. how do u know what quantity of carbon is needed to sufficiently filter a specific volume of water?
not sure if i am stating the question correctly. hopefully u have an idea of what i'm asking.

 

[blkmjk]

It is depenpent on your load requirements. Explained like how many gallons you need and how fast you need them. Commonly referred to as gallons per minute. GPM for short.

What are your requirements? 10 GPM or 10 GPD?

After you determine your load characteristics then you can size your filter accordingly.

In theory if a fish keeper wishes to not alter ph then RO will not be required. If you want to lower your ph and remove chlorine then a RO and carbon combination filter would be best.

My reccomendation would be an sediment filter of 5 microns or better, and a carbon filter for most applications. Sized to the load you expect to operate them under.

Drew

 

[verbal]

A softener is the DI the way that this portion works is you have a resin that has a affinity for iron ,calicum, and other disolved solids. It completes this task through electron exchange and replace ment with sodium ions or Brine as it is called on a typical softener.
So a alternitive to RO is Carbon filtered water. No regenertaive cost IE membranes need to be replaced every 6 months or so. And are costly in most cases.

Hopefully this clears it up a bit for everyone interested in a RODI system. I can go into greater details if needed.

Drew

I am a little confused about DI(De-ionization). Are the Ca ions removed completely or at they replaced with Sodium or Potassium(I think that is the alternative).

Is the DI stage before or after the RO membrane?

 

[Nathan]

http://en.wikipedia.org/wiki/Purified_water#Deionization
You want it after the membrane

 

[verbal]

http://en.wikipedia.org/wiki/Purified_water#Deionization
You want it after the membrane

So DI lowers the TDS even further from just running RO?

 

[Nathan]

Yep, most people wont need it for fish.

 

[blkmjk]

http://en.wikipedia.org/wiki/Purified_water#Deionization
You want it after the membrane

I personally wouldn't reference wikipedia for clarification on this subject.

As a professional installer of industrial RODI systems I have personally never seen DI before the membrane. And there is a good reason why. It is because of the membrane design. The passages that flow water through are just too small. You want to remove absolutely everything possible before it goes through the membrane. The only thing that should pass through the membrane is ultra pure h2o. Thus eliminating the need for further filtering or softening.

http://lttechnologies.com/faqs

These are the type of systems that I install commonly and I would definitely call them an authority.

Drew

 

[Nathan]

I'm pretty sure those big individual models are different than what we use for aquariums

 

[Tony]

Drew,

To be clearer, I'm looking to make at least 75-100 gallons per week with my setup. I'll be using it for my 150 which has South Americans that like their pH super nasty low. Ideally, I'll keep the pH around 6.0, but would like to be able to get the pH down around 5.0, so low the RO membrane is a must, correct?

For my setup, I'm planning on purchasing the bulk pack that Franny posted:

http://www.aquasafecanada.com/store...embranes-beads/aquarium-ro-filters-case-of-18

The sediment filter that comes in the set runs from 20 microns down to 5 microns ans the two carbon cartridges are 5 microns and 1 micron respectively.

Then I was going to replace my RO membrane with this:

http://www.aquasafecanada.com/store...ranes-beads/aquarium-reverse-osmosis-membrane

That should get me rolling, right?

 

[Nathan]

Tony, It looks be cheaper to buy it all from the link I posted