Holycra$ my water TDS level... (1 Viewer)

[fishcraze]

Well going through my spare stuffs in the garage and found an inline dual TDS meter (that can mearsure both inlet/outlet TDS) that I bought last year but never installed it. So I went ahead install the meter on my RO unit for my tank. I was shocked to see the inlet TDS was 188 ppm and outlet was 137 ppm! I haven't checked my TDS for a long time (probably 2 yrs) so not sure how long the outlet TDS has been this bad, but I noticed i had issues with hair algea in my tank for quite a while now and thought it's just b/c the old tank syndrome. Usually the outlet TDS supposed to be ~20-30ppm when the 150 GPD membrane was working properly. So I called Airwaterice.com where I bought the membrane, they told me I bought it back in 2007 so it's way overdue for a new membrane since they normally lasts 3-4 yrs.
What surprised me is that my tank/corals seemed to handle this crappy water just fine - especially many of my rare SPS species! except the nuisance hair algea. Hopefully with a new membrane I'll be able to get the algea problem in better control. For those with RO/DI system out there, don't be scared to death if you see your RO/DI system TDS go up just a bit.. I remember seeing some threads here where people were screaming that there water TDS has gone to 10 ppm! I was in that mode back then when I started my tank with RO/DI system. After couple years with spending too much money/work on replacing the DI resins, I decided to eliminate the DI from the water filter system and run the tank ~20-40ppm with RO only, and didn't see any issue for the last 6-7 years other than saving me a lot of money from DI resin replacement! just my 2 cents

 

[flexrac]

When I had my 110 gal, my Tds was 10-15 on the output, this was due to my di resin laying sideways, funny thing, I never had algae problems. Now I get 0 Tds and I have algae issues in my 90.
I think your tank is so mature, it's doing what it suppose to do.

By the way it was with the help of russ that i got my TDS down.
he helped me re-route my ro unit plumbing and made me change my di resin canistor to a vertical canister from a horizontal.

 

[fredG]

My TDS reading is 45, I don't know if it's contributing to my algae problem or if I need to get my gfo up and running. I will be changing the filters to my ro/di soon though.

 

[steveb]

lol and I was having a fit when my tds reading was 2...

 

[Buckeye Hydro]

I was shocked to see the inlet TDS was 188 ppm and outlet was 137 ppm! I haven't checked my TDS for a long time (probably 2 yrs) so not sure how long the outlet TDS has been this bad, but I noticed i had issues with hair algea in my tank for quite a while now and thought it's just b/c the old tank syndrome. Usually the outlet TDS supposed to be ~20-30ppm when the 150 GPD membrane was working properly.

Hmm. If your feedwater is 188 ppm, with a 150 gpd membrane your RO water should be less than 8 ppm (not 20 to 30 ppm!), and your DI should read 0 ppm TDS.

Russ

 

[fishcraze]

Hmm. If your feedwater is 188 ppm, with a 150 gpd membrane your RO water should be less than 8 ppm (not 20 to 30 ppm!), and your DI should read 0 ppm TDS.

Russ

You are right if the 150gpd working properly, the outlet should be less than 10 ppm with an inlet of 188ppm. I looked at the TDS again the last couple days and the inlet fluctuate ~190-210ppm and the outlet ~125-140 ppm. I was surprised that my tap water inlet TDS is that good now. It used to be around 300-400 ppm on the inlet back then, and the outlet would be more or less 20ppm. Don't know when this change in tap water TDS has happened. My water company must have changed something that somehow the TDS has improved much. I haven't used DI for a long time so my outlet water never gets to 0ppm.

 

[maconbits]

Dude my tds reads out 1 ppm and I go nuts lol. Your crazy Quoc lol

 

[Buckeye Hydro]

Sounds like you're past due for a new membrane.

 

[Mark L.]

I change out all my filters on e a year and have never seen 1 TDS. Always 0.