Tds not at zero

[reef tank 2.0]

Next step im taking to eliminate my algae issue. Last resort, then what????

I have a 4 stage rodi unit. I just put brand new filters in place that i got from BRS, along with a new membrane.

I am running water through it now into the drain till i see 0ppm from tds meter 2 and 3. Its been running for awhile now and tds 2 is reading 8ppm, and tds 3 is reading 8ppm as well.

Why are these not reading 0 ppm?

 

[reef tank 2.0]

I Closed the drain valve and have it going to a bin which would be fresh water bins that i use for tank water. Once i did that, the final tds meter 3 is reading 0ppm. But the tds 2 is still high.

Whats the deal with tds 2?

 

[Freenow54]

Next step im taking to eliminate my algae issue. Last resort, then what????

I have a 4 stage rodi unit. I just put brand new filters in place that i got from BRS, along with a new membrane.

I am running water through it now into the drain till i see 0ppm from tds meter 2 and 3. Its been running for awhile now and tds 2 is reading 8ppm, and tds 3 is reading 8ppm as well.

Why are these not reading 0 ppm?

Do you have a DI filter ?

 

[reef tank 2.0]

Ya,
di, carbon, and sediment

 

[Freenow54]

Yes I looked it up so sorry cant help you unless the flow is not going through the filter

 

[Randy Holmes-Farley Verified Community Expert]

I dont think the tds has much bearing on algae issues, but tds above zero with a new di (after running for a bit to flush it out) means it is hooked up wrong, or not packed right or for some other reason water is channeling through it and not making full contact.

It is a mixed bed di?

 

[reef tank 2.0]

Id like to think the algae isnt from high tds, but im losing hope.

What is a mixed bed di?

 

[diverjm]

Id like to think the algae isnt from high tds, but im losing hope.

What is a mixed bed di?

Mixed bed is when the Cation and Anion are mixed together as a single DI stage. Some Di’s are only mixed bed, others have the two in separate stages. The BRS one I have has 3 canisters (Cation, Anion and the final is a mixed bed).

 

[diverjm]

I’ll also ad, my RO gets my TDS down to 1ppm. Post RO, The first stage of my DI shows 1ppm, the second usually shows 2-3ppm until it has ran for approximately 2 mins. The end stage always shows 0ppm since it’s a final mixed bed.

 

[reef tank 2.0]

this is all I am seeing:

NeoPure Sediment Pre-Filter

Utilize sediment pre-filters to protect the more expensive carbon blocks and to prolong overall filter set life overtime.



Carbon Block

BRS Universal Carbon Blocks are manufactured using high performance catalytic active carbon combined with a new binder system technology which maximizes the availability of the critical catalytic sites. The combination of advanced carbon technology, increased volume of carbon contained in each filter and proprietary manufacturing processes delivers exceptionally high chloramine, chlorine, VOC and general chemical performance.

• NSF Certified
• Specifically formulated for superior Chloramine reduction
• 1 µm (micron) Nominal Filtration*
• Chlorine 35,000 @ 1 GPM**
• Chloramines 3,500 @ 0.5 GPM***
• High chemical adsorption
• 30% more carbon than standard blocks****

Color-Changing DI Resin

BRS Color Changing Resin is packaged in foil-lined 4mm Mylar bags and vacuum sealed to maintain maximum storage life and effectiveness.

• Changes Color from Blue to Brown as the media is exhausted.
• 2 year shelf life (unopened)
• Total Cation Capacity: 1.9 meq/mL min (Na+ form)
• Total Anion Capacity: 1.25 meg/mL min (cl+ form)

this is the RODI kit I purchased: https://www.bulkreefsupply.com/brs-4-stage-universal-ro-di-replacement-filter-kit-bundle.html

 

[diverjm]

That is mixed bed.

 

[diverjm]

Did you flush the membrane and carbon filters before sending it through the DI?

 

[reef tank 2.0]

I put them directly into the rodi containers and then ran water for about 15 minutes, waiting for tds to hit 0

 

[diverjm]

I’m l not positive but I believe 1 TDS is your source water, 2 TDS is post RO and 3 TDS is post DI on your unit. 2 PPM tds post RO is pretty good.

 

[reef tank 2.0]

Yes, that is correct

 

[diverjm]

As long as you’re seeing 0ppm on 3 TDS then your water that you’re collecting is good to go.

 

[t5Nitro]

Can we get more details of your tank set up? From your algae post on 1/26/26, the rock in your tank photos suggest dry rock startup that too long ago. Even if within the last 0-2 years, this could be immature dry startup tank issues that needs more time.

 

[Randy Holmes-Farley Verified Community Expert]

Packing that mixed bed resin tightly into the di cartridge is important. Just pouring some in may be inadequate.

 

[reef tank 2.0]

Well, i am hitting my two year anniversary on March 1st.

I had a larger tank before this one that was up and running for 2 years and i never saw what i am dealing with. Not sure if tank size mattered. But this is definitely a first.

But yes, it was a dry rock set up.

 

[reef tank 2.0]

Packing that mixed bed resin tightly into the di cartridge is important. Just pouring some in may be inadequate.

I made sure to tap and pack it tight after each pour