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loves saltwater
08/20/2007, 06:21 PM
I just received my new meter and the readings are as follows.


top-off water - 55

tank water - 192
virginiadiver69
08/20/2007, 06:23 PM
Your top off should be 0 or as close as possible. Your tank water will naturally be higher with salt.
bertoni
08/20/2007, 06:29 PM
The tank water reading likely is meaningless since it's probably out of range for the meter. What kind of meter is being used, and how has it been calibrated, if it's been calibrated?
loves saltwater
08/20/2007, 06:48 PM
The meter is a handheld made by HM Digital. the range is 0-9990 PPM. it is calibrated with NaCI 342 PPM if that helps
bertoni
08/20/2007, 06:57 PM
If you're getting 55 ppm after a RO-DI filter, that's a major problem. Otherwise, it sounds like moderately clean tapwater. The reading in the tank is meaningless, since the TDS is well beyond that scale.
jsr
08/20/2007, 07:08 PM
I am getting 200 PPM+ from tap, about 10 PPM after RO, and 0 PPM after DI. I hear that testing TDS meter in saltwater can mess with the readings. I could be wrong, but I dont want to risk it.
loves saltwater
08/20/2007, 07:13 PM
I just checked my tap water and it was 386 ppm

The 50 ppm top off water came from the LFS that I used to do business with hehehehe I guess it is time to by an ro/di system...
bertoni
08/20/2007, 07:15 PM
I've never regretted getting mine. :)
jsr
08/20/2007, 07:16 PM
Oh yeah. Be nice and tell them what what you found. They should change the pre-filters and/or membrane. Remember, they are selling this to others.
loves saltwater
08/20/2007, 07:19 PM
Yea I just got off the phone with them to let them know they have a problem. Could this be why I have a touch of cayno also ?
bertoni
08/20/2007, 07:19 PM
Maybe. It all depends on what that 55 ppm of TDS actually is.
loves saltwater
08/20/2007, 07:23 PM
do you care to elaborate on this Bertoni ?
bertoni
08/20/2007, 07:37 PM
Well, if the TDS is a bit of salt or perhaps some plasticizers leached from a container, that might not hurt anything. If a lot of it is phosphate, then that'd be a major problem.
jsr
08/20/2007, 07:51 PM
P04 is bad! I struggled with this before I changed my filters. Phosphate will bring Algae, you dont want that. I was getting a 0.5 reading from the RODI before I changed the filters and tested the TDS. I actully run some PhosGuard in my RODI container before I mix my salt.
Randall_James
08/20/2007, 08:55 PM
Do keep in mind that your RO/DI unit is not maintainance free...

The post RO water in the units I have seen (at least decent ones) run between 5 and 10ppm.. A standard DI unit will hold about 3000P. At this point the PPM reading goes from 0 back to what the post RO reading is. (I get about 500G of good water out of each charge on mine)

The 6PPM I get out of my system I am sure would be ok for the tank but I like the 0 reading (at least with the resolution of my TDS meter)