RODI Units

[BBReefer]

Need to buy RODI unit anybody have recommendations? Pros and Cons? Cost vs Benefits? Accessories needed (TDS Meter, pressure gages, etc)? Where to buy(Local or Online)?

[(Bio)³]

Brs has a good sale last I saw. Bout 150 comes with Tds inline meters, wrenches and such.

[Buckeye Field Supply]

Here are some things to look for in a good system for this hobby:

No more than 4 stages (sediment, carbon, RO, DI) unless you have specific water quality issues you want to address

Standard-sized prefilters, membrane, and DI cartridge

Brand name, high-rejection membrane

Specifications provided for each stage

Pressure gauge after the prefilters and before the membrane

Thermometer

TDS meter (handheld or in-line)

DI bypass

Vertical DI stage

Refillable DI cartridge

Rust-proof bracket

Quick connect fittings

No water from pressurized storage container delivered to DI

Flush valve

Clear housings

High-quality instructions written in clear English

Customer support before, during, and after your purchase

A vendor involved in your hobby

As far as where to buy - we're more than a little biased on that issue so we'll just hush!

Russ

[BBReefer]

Russ... Thanks for the input. What are the differences between a 4 stage or 5 stage? Also, What is the thermometer for? I also believe the city of Round Rock is utilizing Chloramine.. Through my research there specialized RODI for use with Chloramine.

[esacjack]

Filtration stages vary on placement, but generally,

Stage 1: 5 Micron Sediment Filter

The raw tap water first flows through a 5 micron particle FILTER to remove dirt, dust, rust, suspended substances, sediment and floating matters larger than 5 microns.

Stage 2: Activated Carbon Filter

Removes sediment over 5 Micron – Removes odours, bad taste and smell plus any excess chlorine and chemicals.

Stage 3: Carbon Block Cartridge

When water is forced through the solid carbon block, it is forced to slow down and increase the contact time with the carbon, allowing the carbon bonding to take place to reduce certain chemical pollutants like toxic, pesticides, THM’s, chlorine, bad tastes, odours etc.

Stage 4: Reverse Osmosis Membrane

The process works by forcing water under great pressure against a semi permeable membrane, where ion exclusion occurs. With ion exclusion, water molecules form a barrier that allows other water molecules to pass through while excluding most contaminants.

Stage 5: In-Line Carbon Filter

The carbon takes out 99% of the chlorine and organic chemicals

Removes any remaining odours, bad taste and smell

I personally use the 5 stage BRS system with dual TDS meters. I purchased the kit that comes with the water storage, but it isn't needed. I paid 179 for the kit.

http://www.bulkreefsupply.com/brs-5-stage-plus-ro-di-system-75gpd.html

They also have a 150 GPD system. But keep in mind you'll need a place to store all this water, plastic 55 gallon drums work well. A good investment would also be an RO/DI float valve cutoff, an extra Murlock T fitting, and an extra Murlock gate valve (for flushing the system before use see: TDS Creep )

[DerrickH]

A 4 stage should be:

Stage 1: .5 Micron Sediment Filter

Stage 2: .5 Micron Carbon block

Stage 3: Membrane

Stage 4: Di Resin canister

[BBReefer]

Derrick...thanks for the info. I read about flushing the system but did not know exactly how to set the plumbing up.

[BBReefer]

How do you flush the system? Do you run water around the ro membrane and discard it so it wont go throught the ro membrane and di? D

[BBReefer]

How do you flush the system? Do you run water around the ro membrane and discard it so it wont go throught the ro membrane and di? D

[esacjack]

on a 5 stage, you take the line coming from the membrane and T it off. You take one end and insert it into your last stage (filter) the other end of the T should have a valve placed on it so you can turn it on and off. The feed line with the valve should feed into either a drinking water storage container, or a drain. Before collecting any water for the tank, just turn the valve to bypass the flow into the drain. The first time you use the RODI system you'll want to run it for about 30 - 45 minutes in flush mode before collecting any of the water. After the first initial break-in cycle, you'll only need to flush the system between uses. Monitor the TDS meter on the "IN" side and wait for it to drop as close to zero, if not zero, as possible.

Here's a generic video to help you along

[BBReefer]

Ok... I now understand how to flush each stage of thr RO/DI. Once the system is running, I have seen on the internet is to flush they RO system after the last stage of the RO. Is this correct? Do you flush the DI?

[esacjack]

No, you dont need to flush the DI side of things. The reason behind flushing just before the DI is to lower the total TDS going INTO the DI Resin. This extends the life of the DI resin.