Feedback on this product

[kiwis]

I asked for feedback on a RO/DI system earlier in the week and the replies were very helpful.

Much the same, hoping to get feedback on this

http://shop.sentrywaterfilters.com....osis-System-Medium-Portable-RO-DI/p/112264383

 

[TheEngineer]

Do you have a specific question?

 

[kiwis]

Sorry, I'm seeking some feedback on how good this product is. Price seems very reasonable.

 

[TheEngineer]

Seems like a standard unit. I can’t find specs on the RO membrane it comes with. You want one with a 98% or higher rejection ratio.

 

[kiwis]

Seems like a standard unit. I can’t find specs on the RO membrane it comes with. You want one with a 98% or higher rejection ratio.

When I search their online shop I can find replacements which show specs... any good?

http://shop.sentrywaterfilters.com....lement-Filters-USA-NSF-RO-Membrane/p/84819807

 

[TheEngineer]

That’s a 95% rejection rate membrane. Do you know what your incoming TDS is?

 

[kiwis]

That’s a 95% rejection rate membrane. Do you know what your incoming TDS is?

I've never tested it before, I'm in Auckland, New Zealand I've read reports of anything between 35 and 55 but not idea if this is true

 

[kiwis]

A google search of WaterCare (water services)

Total dissolved solids: (mg/L)
Average; 76.88
Max: 116.5
Min: 58


https://www.watercare.co.nz/CMSPage...af2b7975c9b7992230075f0e39d38f457a435113cc9e9

 

[TheEngineer]

I had a feeling you were in New Zealand based on the name. I’ve been once before and really liked it. One of the few work trips when I actually had time to explore a bit.

I was there seeing Peter Beck at Rocket Lab before they were a big deal


DI cartridges can take out about 2000 TDS total. At 116 TDS here’s how long DI would last you (round about):

333 gallons at 95%
575 gallons at 98%

That 3% rejection really adds up quickly. That turns into a 58% loss in capacity.

 

[kiwis]

I had a feeling you were in New Zealand based on the name. I’ve been once before and really liked it. One of the few work trips when I actually had time to explore a bit.

I was there seeing Peter Beck at Rocket Lab before they were a big deal


DI cartridges can take out about 2000 TDS total. At 116 TDS here’s how long DI would last you (round about):

333 gallons at 95%
575 gallons at 98%

That 3% rejection really adds up quickly. That turns into a 58% loss in capacity.

Yeah NZ is a cool place, could live anywhere else.

Why would it last longer at 98%?

Either way, I'll be needing 20L a week so will last 12-14 months which is a good time. More interested to know if this will give me good water quality.

 

[TheEngineer]

The difference is how much TDS has to be removed by your DI.

 

[kiwis]

The difference is how much TDS has to be removed by your DI.

So 98% removed it lasts longer? I don't get it. I thought that would work harder and last less.

 

[kiwis]

How about this unit?
https://www.trademe.co.nz/pets-anim...95.htm?rsqid=ba14af2e3b9b480f9b06b491678027fa

 

[TheEngineer]

So 98% removed it lasts longer? I don't get it. I thought that would work harder and last less.

The 98% number is how much TDS is removed by your RO membrane. Any TDS not removed by the RO needs to be removed by the DI.

 

[Water Dog]

The one in the first link looks like it has a horizontal inline DI cylinder. These are not the most efficient DI stages as the RO water tends to channel through the media. Look for an RODI unit with a DI stage in the standard canister, like the canisters for the prefilters. Water will flow more evenly through these style of DI canisters utilizing all of the resin evenly.

Not a fan of the second unit linked as it appears to use all proprietary filtration cartridges which will each cost more, significantly adding to the total expense over the lifetime of running the unit.

 

[kiwis]

The one in the first link looks like it has a horizontal inline DI cylinder. These are not the most efficient DI stages as the RO water tends to channel through the media. Look for an RODI unit with a DI stage in the standard canister, like the canisters for the prefilters. Water will flow more evenly through these style of DI canisters utilizing all of the resin evenly.

Not a fan of the second unit linked as it appears to use all proprietary filtration cartridges which will each cost more, significantly adding to the total expense over the lifetime of running the unit.

So this is better?
https://www.trademe.co.nz/Browse/Listing.aspx?id=1882676228

 

[Water Dog]

That still looks like the DI stage is a horizontal inline. You could see it hooked up on top of the RO housing.

 

[kiwis]

Oh Horizontal.... read that as vertical for some reason.

So far from here and on facebook groups I've questioned about 10-12 units. All have faults.

Can someone recommend a good unit?

 

[Water Dog]

Do you see how the 3rd canister is a vertical DI unit? In addition, the TDS meter and pressure gauge is a bonus.

https://www.bulkreefsupply.com/4-stage-value-plus-ro-di-system-bulk-reef-supply.html

https://goo.gl/images/vMfTMj