TDS went up.... What now

[Seanybaggs123]

Hey all,

I am using a BRS 4 stage RODI system that I bought used when I bought my setup.
In the past couple weeks my TDS on the output side have risen from 4ppm to 24ppm. My question is, what should I be replacing to remedy this?

 

[scottedontknow]

how old is the unit (before you bought it) ? im assuming when you got it you didnt change out all the filters and resins?

 

[Seanybaggs123]

how old is the unit (before you bought it) ? im assuming when you got it you didnt change out all the filters and resins?

He said he had the tank 5 years.. I imagine the rodi for the same length of time.

I did not change out the filters and resins

 

[Tamberav]

Hey all,

I am using a BRS 4 stage RODI system that I bought used when I bought my setup.
In the past couple weeks my TDS on the output side have risen from 4ppm to 24ppm. My question is, what should I be replacing to remedy this?

Since you bought it used.....I would just replace everything except the membrane.

I generally replace my prefilters every 6 months and DI yearly. I honestly do this even if TDS is zero because the filters are pretty cheap from Marine Depot. I got some diatoms when I let it go too long previously.

How long it will last for you will vary.

 

[Seanybaggs123]

does anyone have any reference material that would point me in the right direction as far as what to buy and how to change it? (is the DI resin a cartridge?)

 

[Uncle99]

Depends on the TDS from the tap. If your tap is say 600....reject rate 96%....then that would be TDS of 24.
Assuming your tds from tap is say 100-400, then, I would replace the membrane and while your at it, the sediment and carbon filter cause they are cheap.
Most good membranes have a good rejection rate 96-99% so in general your membrane does most of the work to get you to say 7-15tds.....then your DI takes you from the 7-15tds to 0-1tds.

Think your memebrane as the workhorse, and the resin the polisher....

 

[scottedontknow]

thats your issue. you should replace youre filters and resins. I always buy the color changing resins as they make it easy to tell when they need to be changed. also if the RO membrain is 5+ years old it could be time for a new one (all depends on how much water was being made over those years, but i think 5 years its time for a new one)

 

[scottedontknow]

here you go.
https://www.bulkreefsupply.com/brs-4-stage-value-replacement-filter-kit.html
and

75 GPD Reverse Osmosis Membrane - Dow Filmtec

Why does BRS recommend this? DuPont is a leader when it comes to water treatment and filtration. Their 75 GPD membrane has a 99% rejection ratio, and most other membranes cannot make that same claim. Along with meeting NSF/ANSI standards the 75 GPD DuPont (formerly Dow Chemical) membrane is...

www.bulkreefsupply.com

 

[JoshH]

As mentioned above, just replace everything. Sediment, carbon membrane and DI. This way you're starting fresh and you know the age of everything. (At 5 years everything is really toast at that point). Bulk reef supply is a good resource for these replacements so is Spectrapure and buckeye Hydro, lots of places to go to. BRS has videos on how to replace everything properly..

 

[JoshH]

Most good membranes have a good rejection rate 96-99%

I'll add that typically a good rejection rate for quality membranes is 98% or higher. 96% is average and what most consider a failure (Replacement) point for quality membranes.

 

[JoshH]

Perfect timing Spectrapure has a little sale going on right now....

SpectraPure - Innovators in Water Technology

SpectraPure, Inc. is an Industry Standard in the Water Purification world. From Drinking Water to Aquarium Systems, you don't just want pure water, you want the PUREST Water! Get it with SpectraPure!

www.spectrapure.com

SpectraPure - Innovators in Water Technology

SpectraPure, Inc. is an Industry Standard in the Water Purification world. From Drinking Water to Aquarium Systems, you don't just want pure water, you want the PUREST Water! Get it with SpectraPure!

www.spectrapure.com

 

[Seanybaggs123]

Thanks Everyone!