Increasing Flow Rate in Contained RODI System

[rsmbudgetbuild2024]

Hello All,

I have a contained RODI System which I call contained because I have a preference to NOT tap into my homes stock pipes or bathroom faucet taps.

Instead, I am using a 1/6HP submersible pump in a Rubbermaid bin which I call the “Untreated Reservoir”.

Inside the untreated reservoir I have added in an air stone which does a tremendous job of keeping bacteria away. Eventually I want to upgrade this to a cylindrical ~40-50 gallons with a dome lid. But for now it is what it is.

I have a waste water line that runs to the laundry machine drain pipe though I must say I have never seen a drop of water even come out of it when it’s in RODI filtering operation which is weird because people say the system produces a lot of waste water:

I am running a 50GPD RODI filter but it is NOWHERE near that figure. I am getting a very consistent 50 drops per minute water production rate and this system is able to create 5 gallons of RODI water in approx 2-3 days.

I am considering getting a small booster pump and a gauge and am wondering about placement to achieve a much better flow rate for my custom system. Here is a diagram to better visualize:

1= input from submersible pump
2= bottom of sediment cartridge outlet
3=bottom of carbon cartridge inlet
4=top of carbon cartridge outlet to RO buddie
5=top of RO Buddie inlet. gravity filters down to waste and DI filter cartridge
6.waste = waste water outlet at bottom of RO buddie (this system produces nearly zero wastewater)
6= outlet to DI cartridge also at bottom of RO buddie
7= inlet at bottom of DI cartridge
8= outlet at top of DI cartridge and out to filtered RODI 5 gallon bucket.

Let me know if anything is not setup correctly as well here.


Some things I have considered to increase flow:
- Adding in a laundry hose to add some distance from the pump to the inlet for the first chamber on the RODI.

Have not tried this yet because the hose I have is metal and would rust underwater. The water coming in from the pump seems powerful but I was under the impression it’s just a pond pump and can do similar water pressure to household. It could shoot water about 60-80ft out of that 1/4” RO pipe pressure seems good but could be too high?

Anyways thanks for stopping by. Hope to learn some new things about RODI filtration and flow rates.

 

[Fish Fan]

Friend, all you need is an adapter like these that matches a faucet in your home, and you can easily attach and remove your RODI filter as needed, without making any drastic changes to your home's plumbing. There's several styles of these adapters, here's two common examples:

Mur-lok Garden Hose/Utility Sink Adapter

Two Sizes Available: 1/4" Push Connect x 3/4" Garden Hose 3/8" Push Connect x 3/4" Garden Hose Mur-lok RO fittings are the only RO fittings that feature dual EPDM O-rings to ensure a straight leak free fit. These high-quality American made fittings are constructed with FDA approved...

www.bulkreefsupply.com

Chrome Faucet Diverter Valve

Diverter Valves are used to attach RO systems to most kitchen sink faucets. They allow RO units to remain connected to the sink. Simply turn the diverter valve lever to operate the RO unit and push back to use the sink faucet. This item is designed for use with our saltwater aquarium line of RO...

www.bulkreefsupply.com

Good luck!

 

[KStatefan]

You need more pump.

Why not hook it up to your house supply

 

[UncommonSense]

To help clarify some confusion here:

A sump pump does not produce anywhere near home water pressure!

1/6hp pump: MAYBE 20ft max vertical well height; <9PSI…

City water pressure (faucets and taps): usually 45-65PSI

— After switching to city water pressure: if more performance is desired, add a booster pump to run the RODI system more efficiently @80-95PSI!


Don’t use this sump pump long-term… it’s going to burn itself up trying to move water against so much back pressure… it is essentially just trying to boil water inside the volute via pump cavitation… — the low pressure will also rapidly degrade your RO membrane!

 

[KStatefan]

Pump curve for a little giant 1/6 HP utility pump. Zero flow at 11.43 psi

 

[rsmbudgetbuild2024]

A lot of really good information is being shared.

It seems my pump is way underpowered with regards to flow. At around <10psi.

Would an in-line pump get me to the flow I’m looking for to get directly to the 80+psi this filter runs highest flow on? Or is it better to get an in-line pump that that does 40-50psi and use a booster pump with that?


I prefer not to tap in to my house supply because these filters create tremendous back pressure. I know it is well within the pipes’ in my house tolerance but just don’t want to add the stress and I like the idea of an untreated tank that can be aerated and I can visualize the water I use better. I could consider a timer or something like that to control adding more water to the storage tank but want to avoid going directly system to supply I want an intermediary storage tank system.

 

[KStatefan]

A lot of really good information is being shared.

It seems my pump is way underpowered with regards to flow. At around <10psi.

Would an in-line pump get me to the flow I’m looking for to get directly to the 80+psi this filter runs highest flow on? Or is it better to get an in-line pump that that does 40-50psi and use a booster pump with that?


I prefer not to tap in to my house supply because these filters create tremendous back pressure. I know it is well within the pipes’ in my house tolerance but just don’t want to add the stress and I like the idea of an untreated tank that can be aerated and I can visualize the water I use better. I could consider a timer or something like that to control adding more water to the storage tank but want to avoid going directly system to supply I want an intermediary storage tank system.

You will not be adding any stress to your plumbing.

 

[UncommonSense]

I prefer not to tap in to my house supply because these filters create tremendous back pressure. I know it is well within the pipes’ in my house tolerance but just don’t want to add the stress

Every valve in your house effectively does the same thing when partially opened; it’s not a matter of the home plumbing being sufficient!

These filters are restrictive to flow, but that is by design! — the only real concern is a possibility for a leak at any pressurized fitting; this is why some choose to only hook up (or just pressurize) their RODI when they need to make water!

I, personally have had my RODI hooked up directly to my home plumbing and pressurized for over a decade with zero issues!

If you want to see the water supplying the RO, you can simply add a sediment pre-filter with a clear housing!

— (Here’s exactly that on my RODI; 5micron pre-filter for 1micron)

Would an in-line pump get me to the flow I’m looking for to get directly to the 80+psi this filter runs highest flow on?

It looks like the minimum inlet pressure for applicable Aquatec booster pumps is 20psi… so at the very least; a dedicated pressure rated lift pump would be necessary! — these get pricey fast!

 

[Fish Fan]

You’re making needles work for yourself here. Many, many reefers connnect an RODI to their house either permanently or temporarily.

 

[rsmbudgetbuild2024]

At a current rate around 10psi I would appreciate even a +20psi boost to around 30-40psi or less than that even. Enough to get a constant stream I’d be happy with. as super high flow output rates could affect TDS imo.

Going in line seems like the way forward here also because the submersible creates heat and may wear the DI filter faster. It will move more water volume faster so I may have to upgrade to a larger untreated tank to compensate having to fill it up quicker.

I am inspired by larger systems that use storage tanks. I thought maybe a small booster with lower thresholds on the current system could get me to at least 20psi

 

[Fish Fan]

At a current rate around 10psi I would appreciate even a +20psi boost to around 30-40psi or less than that even. Enough to get a constant stream I’d be happy with. as super high flow output rates could affect TDS imo.

Going in line seems like the way forward here also because the submersible creates heat and may wear the DI filter faster. It will move more water volume faster so I may have to upgrade to a larger untreated tank to compensate having to fill it up quicker.

I am inspired by larger systems that use storage tanks. I thought maybe a small booster on the current system could get me to at least 20psi

Yes, you're needlessly fighting an uphill battle by how you're trying to do this here

You want your RODI to be above about 70 psi to a max of about 90 psi for it to function correctly. The higher the better in terms of filter efficiency, but obviously too high can crack fittings and then you could get a leak, so keep it under 90 psi to be safe.

Did you see my suggestions above for a way to very simply connect your filter to your faucet? You can add it and remove it each time you make water, or leave it in place more permanently. I would hook your filter up that way and see how much PSI you're getting. If you're only getting like 40-50 psi or so, this is then a good place for an RO booster pump.

 

[UncommonSense]

At a current rate around 10psi I would appreciate even a +20psi boost to around 30-40psi or less than that even. Enough to get a constant stream I’d be happy with. as super high flow output rates could affect TDS imo.

You should do a bit of digging on how these membranes operate! — performance is actually improved the higher your water pressure (up to safe maximum operating pressure of around 110psi)!

In fact, BRS doesn’t really recommend the dual membrane systems without a booster pump at under 65PSI, because it causes TDS creep, and shortens membrane lifespan!

I seem to recall single membranes (at 99% rejection) don’t like running at anything under 40PSI…

These are inherently high pressure, low flow systems… definitely not what a sump pump is intended for!

 

[RocketEngineer]

I prefer not to tap in to my house supply because these filters create tremendous back pressure. I know it is well within the pipes’ in my house tolerance but just don’t want to add the stress and I like the idea of an untreated tank that can be aerated and I can visualize the water I use better. I could consider a timer or something like that to control adding more water to the storage tank but want to avoid going directly system to supply I want an intermediary storage tank system.

I think you have a misunderstanding of how the water pressure system in your house works. The maximum pressure is set at the incoming water, either the well pump or public supply. When there’s no water running, you have infinite resistance to flow. An RODI unit acts like a barely open valve from the point of the water supply. It could care less about the resistance the RODI is causing because the supply is intended to work agains deadheads in order to build pressure throughout the system.

 

[foamboy]

Your system isn’t very efficient. That submersible pump isn’t going to produce enough pressure for the ro membrane and is going to consume more electricity than the 3 gallons per day are worth. Your best bet is to get an adapter to temporarily hook your system to your sink while you are making water.

My system is producing at a rate of 290 gallons per day at a 1:1 ratio. I have 3 75 gpd membranes and a booster pump that I’m running around 90psi. It’s only consuming 44watts to run the booster pump.

 

[UncommonSense]

Your system isn’t very efficient. That submersible pump isn’t going to produce enough pressure for the ro membrane and is going to consume more electricity than the 3 gallons per day are worth. Your best bet is to get an adapter to temporarily hook your system to your sink while you are making water.

My system is producing at a rate of 290 gallons per day at a 1:1 ratio. I have 3 75 gpd membranes and a booster pump that I’m running around 90psi. It’s only consuming 44watts to run the booster pump.

How many ppm TDS is your RO product water pre-DI?