RODI for Apartment Life?

[cdw79]

You can frequently catch the whole unit on sale for $70 with free shipping on Chewy.com or Amazon.

That's part of what kills me a little haha. But do I really need to be replacing the whole unit (or all 4 cartridges, depending on how you look at it I suppose) every 6-8 months? I thought I remember my LFS guy saying only some combination of the cartridges needed to be changed but I'm not sure if that's the case / how I would know which ones to remove when

 

[Reef.]

Depending on the size of tank, you could just buy distilled water from the store.

Cost wise, if you go small, they tend to be expensive, replacing cartridges can also be expensive, as you are limited to what you can buy. You will also be replacing them more often.

I would just buy a normal 4 stage system, replacements are a lot cheaper as you have more choice, they last longer too, and the space they take up is not much more than a smaller unit.

 

[livinlifeinBKK]

For the RO Buddie model I posted I think replacement filters are only like $35 all together on Amazon and they don't need to be replaced more often than other systems despite the compact size

 

[cdw79]

But if I opt to just replace the cartridges, how do I know which ones to replace? Or do you just replace all four each time?

 

[LeftyReefer]

By monitoring TDS at various points in the RO/DI unit, you can determine when the filters need to be replaced.

If you know the TDS of the incoming source water, and what it is coming out of the RO membrane, you know when the RO membrane needs to be replaced. When the DI stage isn't removing the final TDS, it's time to replace that.

your sediment and carbon filters should be changed out more often, since they trap particulates, and will keep your membrane and DI stage working better, longer.

 

[cdw79]

By monitoring TDS at various points in the RO/DI unit, you can determine when the filters need to be replaced.

If you know the TDS of the incoming source water, and what it is coming out of the RO membrane, you know when the RO membrane needs to be replaced. When the DI stage isn't removing the final TDS, it's time to replace that.

your sediment and carbon filters should be changed out more often, since they trap particulates, and will keep your membrane and DI stage working better, longer.

So at least as far as I know, my unit doesn't seem to have a way to do that? I may just be being a little slow here admittedly though, so I could definitely be wrong.

Is there a recommended general timeframe for each respective chamber to be replaced? Keeping in mind I only produce ~15 gal a week of purified water (though it does take quite awhile to fill up due to living in an elevated apartment so maybe it goes through more water than is typical)

 

[ScubaFish802]

Late to the party, but posted this on a similar thread yesterday. If you have a washing machine you can split off the cold water side and hook up an RODI from there.

I put two screws into studs in the wall, then slapped together some plywood that was laying around, and hung the plywood ‘frame’ on the two nails so I can easily remove the whole unit when needed.

These filters are supposed to change color as they age, but have barely done so in the last year + of weekly use.

The unit itself was pretty cheap on BRS site during a sale, which they run regularly on their own systems.

Not sure if that gives you any additional options but figured I’d throw it in.

 

[LeftyReefer]

So at least as far as I know, my unit doesn't seem to have a way to do that? I may just be being a little slow here admittedly though, so I could definitely be wrong.

Is there a recommended general timeframe for each respective chamber to be replaced? Keeping in mind I only produce ~15 gal a week of purified water (though it does take quite awhile to fill up due to living in an elevated apartment so maybe it goes through more water than is typical)

It all depends on your source water. the poorer your source water, the quicker your filters will need replacing.

Generally, your sendiment and carbon filters should be replaced most often. Your RO membrane should last a few years provided you take care of it. How long your DI lasts will depend on how good/bad your source water is and how good/bad your RO membrane is working. The more TDS that enters your DI stage, the faster it will deplete.

Some people change their sediment filter and carbon filter every 6 months, others do it yearly. others need to do it every 3 months... it really depends on quite a few factors.

Your RO membrane should reject about 98% of your total TDS if it is working properly. Your DI stage should remove the last few TDS that make it through your membrane.

People have TDS meters to read the TDS of the water. You can buy in-line meters that you can install in your RO/DI system, or you can get a hand held TDS meter and check the water with that.

My RO/DI system has triple in-line meters and I use a hand held checker for spot checking things.
1st meter is on the incoming source water, so I know the TDS of the unfiltered water.
2nd meter is on the output of my RO membrane, so I know how many TDS the RO membrane removed.
3rd meter is after my DI stage, so I know that my DI stage has removed all remaining TDS.

By knowing the source TDS and what it is coming out of the RO membrane, I can tell what % of TDS the membrane is removing.... as long as its around 98% or so the RO membrane is working good and I'm happy.
When I see anything other than 0 TDS coming out of the DI stage, I change my DI resin.