Normal TDS & When To Change RO Filters

[JSkeleton]

Yes the 10" filter will last longer and you have more options then having to purchase propriety filters.

Okay, that's what I thought! I mean, if the 10" will last longer and are the same price AND give me more options, it sounds like a unit that has the 10" ones (such as the picture I posted a few posts up (#63) should save me money in the long run, right?

 

[JSkeleton]

I am changing the sediment and carbon filters as well as it have been 2 years and they are only $7 each.

No indication that they needs changed. Water is still 0 tds.

Your Sediment and carbon have both lasted you 2 years as well? :O

That's crazy, wow. What kind of water supply do you have and what kind of TDS out of tap?

I'm thinking I may have 4ppm TDS due to my city water having some traces of Chloramine (might need a different kind of carbon filter).

 

[LeftyReefer]

Chlorine and chloramines are my biggest concern with my water, which is why I run double carbon blocks.

 

[Acros]

Your Sediment and carbon have both lasted you 2 years as well? :O

That's crazy, wow. What kind of water supply do you have and what kind of TDS out of tap?

I'm thinking I may have 4ppm TDS due to my city water having some traces of Chloramine (might need a different kind of carbon filter).

About 70tds for year 1, then we loved to a new city that uses RO filteration. Tds is about 30.

 

[JSkeleton]

Chlorine and chloramines are my biggest concern with my water, which is why I run double carbon blocks.

The guy at Aquatic Life told me only a "Carbon Plus" would remove chloramines though? Unless I misunderstood and a double carbon would do the same.

That said, if my 4ppm TSD is from that, in theory, either a Carbon Plus or double Carbon may bring me to 0ppm and not need a DI?

 

[JSkeleton]

About 70tds for year 1, then we loved to a new city that uses RO filteration. Tds is about 30.

Oh wow, that sounds like a great city! But even at the 70tds for 1 year, your filters were lasting you a while eh?

 

[Acros]

Oh wow, that sounds like a great city! But even at the 70tds for 1 year, your filters were lasting you a while eh?

Yeah, my tank is a 25 gallon, so I don’t make a lot of water.

 

[mijan]

Your Sediment and carbon have both lasted you 2 years as well? :O

That's crazy, wow. What kind of water supply do you have and what kind of TDS out of tap?

I'm thinking I may have 4ppm TDS due to my city water having some traces of Chloramine (might need a different kind of carbon filter).

A TDS meter will not detect Chloramines. You would need a chlorine test to see if any came through your RO system.

 

[JSkeleton]

A TDS meter will not detect Chloramines. You would need a chlorine test to see if any came through your RO system.

I should clarify, it was a Rep at Aquatic Life that suggested my 4ppm readings were probably due to my city water saying they use chloramines and that realistically with a special carbon filter, it should be as low as 2-3ppm and then a DI would do the rest.

That said, a chlorine test is for chlorine and not chloramines no?

 

[JSkeleton]

I purchased everything from BRS. The RO/DI unit can be purchased during one of their many sales events for around $380, and the pump kit was around $125.

Question about your Booster. The RODI unit I was looking at says MAX 80 PSI but if the booster brings it up past that, how does that work? Can you somehow manually adjust it so it doesn't go past a limit but still boosts it?

 

[dschuffert]

Question about your Booster. The RODI unit I was looking at says MAX 80 PSI but if the booster brings it up past that, how does that work? Can you somehow manually adjust it so it doesn't go past a limit but still boosts it?

Yes, there is an adjustment on the booster to control output pressure. The factory default is 90 psi and that worked for me. If you wanted to lower the pressure there is a screw for the adjustment. Counter clockwise lowers pressure and clockwise raises pressure.

 

[JSkeleton]

Update question!
I found my City's Water Quality Report, and was wondering if anyone could help me understand it better, and if this would help give a better picture on how fast I would be burning through each filter (Sediment, Carbon *Carbon Plus probably for Chloramines*, Membrane, and if a DI is necessary still and if so how often I may burn through that)? I'm not sure if anyone can even give a better estimate based on this, if not I understand, but if so great!

Link: https://documents.ottawa.ca/sites/documents/files/WQ_table_AODO_Lemieux_2021_2.pdf

 

[Buckeye Hydro]

Add on DI Kit with Color Changing Resin

At Buckeye Hydro we specialize in providing the highest quality water filtration systems and accessories for every potential need.

www.buckeyehydro.com

 

[Buckeye Hydro]

This is copied from our FAQ page:

A good rule of thumb is to replace your sediment filter and carbon block after six months. A more precise way to maximize the usable life of these two filters is to use a pressure gauge to identify when pressure reaching the membrane starts to decline. This is your indication one or more of the prefilters (all the filters that touch the water before it reaches the RO membrane) is beginning to clog.

Also be cognizant of the chlorine capacity of the carbon block. A good 0.5 micron carbon block for example will remove much of the chlorine from 20,000 gallons of tap water presented at 1 gpm. Some original equipment suppliers commonly provide carbon cartridges rated at 2,000 to 6,000 gallons. Remember that all the water you process, both waste water and purified water, goes through the carbon block.

Regarding your RO membrane and DI resin, use your total dissolved solids (TDS) meter to measure, record, and track the TDS (expressed in parts per million [ppm]) in three places: 1) tap water, 2) after the RO but before the DI, and 3) after the DI.

The TDS in your tap water will likely range from about 50 ppm to upwards of 1000 ppm. Common readings are 100 to 400 ppm. So for sake of discussion, let's say your tap water reads 400 ppm. That means that for every million parts of water, you have 400 parts of dissolved solids. How do we go about getting that TDS reading down to somewhere near zero?

If you do some experimenting with your TDS meter, you'll note that your sediment filter and carbon block do very little to remove dissolved solids. So with your tap water at 400 ppm, you can measure the water at the “in” port on your RO membrane housing and you'll see it is still approximately 400 ppm.

The RO membrane is really the workhorse of the system. It removes most of the TDS, some membranes to a greater extent than others. For instance, 100 gpd Filmtec membranes have a rejection rate of 98% (i.e., they reject 98% of the dissolved solids in the feed water). So the purified water coming from your 100 gpd membrane would be about 8 ppm (a 98% reduction). The lifespan of an RO membrane is dependent upon how much water you run through it, and how “dirty” the water is. Membranes can function well for a year, two years, or more. To test the membrane, measure the TDS in the water coming into the membrane, and in the purified water (permeate) produced by the membrane. Compare that to the membrane’s advertised rejection rate, and to the same reading you recorded when the membrane was new. Membranes also commonly produce purified water more slowly as their function declines.

After the RO membrane, water will flow to your DI housing. DI resin in good condition will reduce the TDS in the RO water down to 0 or 1 ppm. When the DI output starts creeping up from 0 or 1 ppm, your resin needs to be replaced. Sometimes you'll hear people complain that their DI resin didn't last very long. Often the culprit is a malfunctioning RO membrane sending the DI resin high TDS water. This will exhaust the resin quicker than would otherwise have been the case. Sometimes the problem is poor quality resin – remember that all resins are not created equal.

Additionally, don’t forget to sanitize the entire system at least once per year, and wash and lube your housing o-rings with food-grade silicone grease every filter change.