RO/DI For The 1st Time

[GoTakeANap]

Just used my unit for the 1st time today. So much easier than going to LFS to buy water. My unit has a TDS Meter built in. The reading on IN was 2-3 and OUT was 0 the entire time. What does this reading mean? How do I determine my TDS?

Also how often should I replace the Filter Media?

 

[redfishbluefish]

My guess is that one sensor is after the RO unit and the second is after the DI unit....this makes the most sense.


You ideally need to know the efficiency of your membrane and the incoming TDS to determine when the membrane is shot. However, knowing that the current reading is only 2 -3, I'd say when you start to see this number climb is when you need to replace your membrane. Similarly, the TDS coming out of DI should be 0 (zero). When this is no longer the case, that's when you need to change out or re-generate the DI. Note that when you first turn on your system the TDS for the RO side might go high for a few minutes....this is normal, but should settle down to the 2 to 3 within a few minutes.


Note that your sediment and carbon blocks need to be replaced more frequently, dependent on the amount of water you make and/or how "dirty" your water is.

 

[GoTakeANap]

just tested my 1st batch of SW.

PH - 8.3
ALK - 12.6
Ammonia - 0 - 0.25 (Cant tell bc its basically inbetween)
Phosphate - 0
Nitrite - 0
Nitrate - 0
Sal - 1.024

My biggest concern is the Ammonia. It should read 0 on a frest batch of water correct?

 

[Mufasa31]

Correct. Ammonia should be 0.

Also, you alk seems high.

 

[GoTakeANap]

Correct. Ammonia should be 0.

Also, you alk seems high.

do you know what ould be causing these 2 numbers to be high?

Guessing the salt water I just made is no good then if the ammonia is reading 0- 0.25?

 

[redfishbluefish]

Wait till tomorrow....and test again. I'm betting it will be gone.

 

[GoTakeANap]

Wait till tomorrow....and test again. I'm betting it will be gone.

Tested the saltwater again today and it still showed the same amount of Ammonia. Also tested my RO/DI water before adding salt on sunday and it showed 0 Ammonia.

Tested the RO/DI water I made today and yesterday and it showed 0 Ammonia. The new saltwater batch I made yesterday, tested it today after letting the salt get mixed in with 2 pumps and it shows 0.25 Ammonia.

So 2 batches of saltwater ive made shows Ammonia after ive mixed the salt in with the RO/DI water. Im a little lost to where the Ammonia is coming into play.

 

[AZDesertRat]

You cannot accurately test RO/DI water with test kits. It is so pure it takes special lab grade instrumentation to do so so this is why a god quality handheld TDS meter is critical. TDS or conductivity/resistivity are our only reliable ways of testing at home. Many salts contain trace amounts of ammonia, pretty common and no big deal.

 

[GoTakeANap]

You cannot accurately test RO/DI water with test kits. It is so pure it takes special lab grade instrumentation to do so so this is why a god quality handheld TDS meter is critical. TDS or conductivity/resistivity are our only reliable ways of testing at home. Many salts contain trace amounts of ammonia, pretty common and no big deal.

TDS meter has read 2 yesterday then dropped to 1 half the time I used it. Today its been 1 all day. Glad to know salts contain trace amounts of ammonia. Did not know that, guess thats one of the reasons I keep coming back here. Learn something new everyday.