Looking for a little RO/DI advice....

[jcl123]

Hello,

I have a Kinetico water softener and a K5 drinking water system. The water softener has pre/post mechanical filters, a ginormous carbon filter, and a two-chamber resin recharge setup. That feeds the whole house, and also the K5.

The K5 produces amazing drinking water, and in theory I think I might be able to figure out where to tap into it to get just raw RO water, and then add just a separate DI stage to then use for top-off and so on. Although they are very cryptic about their setup, so it is hard to get an answer to that question so far.

But, I am wondering what I should add to this for aquarium use. I could either add a whole separate RODI or just DI after the K5. But I am wondering what the water softener does to the equation.

I am thinking either I don't need as many stages in the RODI, or if I had all the stages, they would last a very long time because the water is already starting off pretty good. It's city water to begin with, we got the water softener because it reduces rust in the showers, toilets, washer, and it is nicer to bath in.

Probably I will go somewhere like Spectrapure and see what they say. Maybe they will want me to send them a water sample and then go from there.

Do people like Spectrapure or Bulk Reef Supply? Main thing I want is reasonably priced and readily available cartridges/supplies.

Just looking to hear if anyone has been in a similar situation and had strong feelings on which direction to go.

Thanks

-JCL

 

[azbigjohn]

I am a Spectrapure fan of the highest order (of course they are located 20 miles from me.)

I would think you could tap into the outlet of the Kinnetico system, but I would check to make sure that doesn't void anything on your contract. That being said, it might be easiest to just get a RODI system, knowing you will get better life out of your carbon and sediment filter...

Spectrapure is a little more pricey, but I really think their units are the better quality of the two.

 

[jcl123]

I am a Spectrapure fan of the highest order (of course they are located 20 miles from me.)

I would think you could tap into the outlet of the Kinnetico system, but I would check to make sure that doesn't void anything on your contract. That being said, it might be easiest to just get a RODI system, knowing you will get better life out of your carbon and sediment filter...

Spectrapure is a little more pricey, but I really think their units are the better quality of the two.

Thanks for the quick reply.

Yeah, Spectrapure sells a DI-only unit that is not that expensive, so that might be the way to go.

How long do these DI resins tend to last? I will only really be using it for top-off, I won't be doing many water changes.

-JCL

 

[azbigjohn]

Thanks for the quick reply.

Yeah, Spectrapure sells a DI-only unit that is not that expensive, so that might be the way to go.

How long do these DI resins tend to last? I will only really be using it for top-off, I won't be doing many water changes.

-JCL

Really depends on the amount of dissolved solids in your feed water. Mine last about 9 months, but I change my prefilters rather often, due to high TDS water here in AZ.

 

[Bob Lauson]

I also have a K5 Kinetico system and have used it for years for my top off water. I have added the SpectraPure DI system to the output and I have always been very satisfied. Upstream of the K5 is a water softener. I use what most people don't with respect to top off water. I plumb the K5/SpectraPure output directly to a mechanical float valve. I have a high water switch which my Apex controller monitors. If the high water switch opens, the Apex powers a solenoid that shuts off the water supply to the float valve. I only add this narrative because the K5 has an automatic shutoff once it flows 500 gallons. So I need to be aware of where the filters are at so I am not out of town when the K5 shuts off and I lose my top off.

 

[jcl123]

I also have a K5 Kinetico system and have used it for years for my top off water. I have added the SpectraPure DI system to the output and I have always been very satisfied. Upstream of the K5 is a water softener. I use what most people don't with respect to top off water. I plumb the K5/SpectraPure output directly to a mechanical float valve. I have a high water switch which my Apex controller monitors. If the high water switch opens, the Apex powers a solenoid that shuts off the water supply to the float valve. I only add this narrative because the K5 has an automatic shutoff once it flows 500 gallons. So I need to be aware of where the filters are at so I am not out of town when the K5 shuts off and I lose my top off.

Thank you for your reply.

Yes, you have a very similar setup, I too have a Kinetico water softener before my K5.

I am thinking I can't use my K5 with my aquarium. Even if you put it on the product water output of the K5, such as you are doing (which would count against the 500 gal shutoff as you point out), the water filter company I am working with noted that the flow through the DI resin would likely be too fast.

I think you are getting away with it because you probably draw a small enough amount each time, because you are directly connected to a float valve. Normally I think your setup would not work, because you are not supposed to draw small amounts of water at a time. It causes "TDS creep" because the first bit of water drawn is not completely pure. But this is less of an issue with the K5, because it auto-flushes it's membrane with product water, so you don't get TDS creep.

Do you only use it for top-off? Do you also use it for water changes? Because if you drew many gallons at a time, it would probably go through the DI resin too fast, you might want to check your output TDS to see if it is still 0 in that case.

This is the setup I am considering: https://airwaterice.com/typhoon-iii-aquarium-rodi.html
- A new 5-stage RODI just for the aquarium (pre-filter, 2 carbon stage, RO, and DI)
- Empties into an anti-TDS tank: https://airwaterice.com/tanks-pressure-gauges/anti-tds-storage-tank.html
- Then I was going to use the pump that comes with the Apex ATO kit to go from that tank to the float in the resevoir
- This also gives me a supply of water ready to do water changes as needed

I do have a tip for you though. Instead of going out of the K5 directly, which is the pipe marked in white, if you tap into the pipe marked green with a T, that is direct RO water going to/from the tank before it goes to the post filter. So in this way, you would have unlimited top-off, because it would not count against the 500-gallon shutoff. So you would not have to worry about it.

The K5 doesn't store fully filtered water in the storage tank, it is pure RO water. It only sends it through the last two stages right as you draw water from the faucet.

You would still have the problem of running the water through your DI resin too fast if you drew allot of water, but if you keep drawing small amounts at a time like you are doing, it is probably OK.

It took me a fair bit going back and forth with Kinetico and my water filter supplier to figure that out, so maybe it will help you ;-)

I decided it won't work for me, because you would need to get the water directly off of the RO membrane before it goes to the tank (with a check valve) to use it properly, this is how a regular RODI setup does it, it only goes through the DI stage slowly as the water is produced. But on the K5, there is no way to get to this, because it is buried in the manifold on top.


-JCL

 

[Bob Lauson]

Your comment about the storage tank on the K5 is interesting and I was not aware of that. I will look into it. On your tip above, are you referring to the color codes on the K5 or some other document?

 

[jcl123]

It's the colors marked on the K5 where you plug all the pipes in.

 

[Bob Lauson]

I will look into it tomorrow. First - great dialogue. Second - we need to get a life since it Saturday night at 11 pm

 

[Bob Lauson]

Also in response - I use the water for water changes as well. The TDS always reads zero.

 

[jcl123]

Well, I got back from dinner with my wife, kids, and friends a little while ago, and I am now on my 2nd beer.

Does that not count?

 

[jcl123]

Also in response - I use the water for water changes as well. The TDS always reads zero.

Well, since you have the water softener and the K5 is so good, maybe your water quality is good enough to start with that the DI doesn't have that hard a time getting it to zero. How often do you need to change it?

 

[Bob Lauson]

Ha! I also had a couple of beers and my wife just got back from out of town. Kids grown and moved out. The height on the bar for a good time on Saturday is inversely proportional to your age.

 

[Bob Lauson]

I added the DI only in the last month so have not changed it yet. I will need to do some research to figure out the change interval.

 

[jcl123]

Well, my RODI from AW&I arrived a few days ago, and I am almost done installing it. I did purchase the anti-TDS-creep tank, because I needed a placed to store product water anyways.

-JCL