What are your TDS readings of RO water??

[wombat1]

I just got a TDS meter from Aquatic Reef Systems. Kind of cheesy looking but it reads the calibration fluid right on every time. It reads my RO water in the storage tank as 29ppm and straight out of the unit as 27ppm. I've read about lots of people with readings of zero, but how is this possible?? My RO is a Full size Kent Marine with Hi-s filter and it's been running about 4 months. The water out of the tap is 470 ppm so I guess it's taking out a lot of junk, but is this too high??

 

[aggiefish]

Got the same TDS meter, but my RO/DI unit was from AQR. The TDS meter read 0-1 PPM, you might need to change one of your membranes. Just a guess though

 

[Jimmy G]

I just got my meter from Aquatic Reef Systems also, Is yours a Hanna hand held? It reads my Ro/DI at 3 ppm. Straight from the tap was 300 and something I think..... I calibrated it withe the calibration fluid that came with the meter.

 

[Anonymous]

470 is pretty high to start with. It sounds like your system is rejecting about 95-96%, which isn't too bad considering where you are starting. I have to believe this will shorten it's lifespan. For sure I would use a flush valve if you don't already have one.

My tap water starts out at 26 and ends up at 0, I think my membrane might last a long time. I'm not familiar with the Kent systems, I use a 4 stage unit from Aquatic Reef Systems, including the DI cartridge.

Regards, Eric

 

[Anonymous]

My tap (old house) was 370 ppm. I get a 0 ppm TDS reading when all filters are changed (not the membrane, it's 1-1/2 years old). 3 or 4 months later the reading will be up to 4 or 5 ppm. You are probably in the same boat as me. The DI cartridge is prolly what needs to be changed to get it back to 0. I don't think a reading of 4or 5 is of any concern so I'm not changing my DI for a while longer.

HTH

Louey

 

[Brvheart5]

The meter is cheesy looking?? It looks to me about like I would imagine it...

Anyways, you mention "RO" unit a few times. Is your unit an RO or RO/DI? How many cartridges are there? There is a Hi-S RO and RO/DI.

Basically, in ideal conditions, an RO (Reverse Osmosis) will get you to 10 TDS and an RO/DI will get you to 0 TDS.

So maybe your unit is an RO. A reading of 29 is a bit high for an RO, but not too bad. I have an RO/DI that has seperate outputs for the RO water, and the RO/DI water. My RO water never gets down to 10 either. But then again I haven't tested the RO water since I was breaking it in. But I have a pretty high TDS out of the tap also.

So count the cartridges on the filter. Include the horizontal one lying on the top of the tall cartridges.

If you DO have an RO/DI, I'd be talking to Kent. :evil: Or ARS.

 

[Emperator]

water produced by my ro/di tested at 1ppm as of 10mins ago.

water out of the tap varies from 250-270ppm.

hth

 

[SPC]

Water out of tap = 260ppm
Water out of RO only = 10 ppm
Water out of DI = 1 ppm

If you are getting 27 ppm out of the RO unit then there is indeed a problem. What does your pressure guage read? What is your rejection rate (good water vs rejected water)?
Steve

 

[npaden]

With your tap water being so high in TDS I also think that the 27 ppm reading you are getting is about right from an RO. If you boost the pressure you might do a little better. If you add a DI it will get eaten up 3 times faster than for someone that is getting a TDS of 10 after their RO.

FWIW, Nathan

 

[golfish]

I use a Hanna TDS meter.

225 off the tap
zero off the RO
zero off the RO|DI

 

[Brvheart5]

I use a Hanna TDS meter.

225 off the tap
zero off the RO
zero off the RO|DI

zero out of the RO??? sounds fishy!

 

[monkeyboy]

Kent Hi-S r/o = 2ppm
after Hi-S di = 0

Do you have a flush kit on your unit? A good flush periodically will keep the membrane clean and will usually drop my tds readings a day or so after flushing (flush kits are really cheap!). My r/o read 20+ ppm tds month or so ago, prompting a change (after about 2 years).

 

[wombat1]

My unit is just RO, and I ordered a DI add on from ARS, along with new cartridges. It's a three stage unit. My flush kit just allows me to clean one cartridge at a time, should I just clean the first one???

 

[SPC]

Wombat, the flush kit is just for flushing the membrane which should be your last stage.
Steve

 

[wombat1]

Thanks for the advice guys. I just got my new cartridges and DI add on today. New TDS reading: 0-1ppm!! My tap water is 500ppm.

 

[danmhippo]

Wombat, your tap is very high on TDS! My tap has an average of 180ppm and after RODI, 0ppm.

 

[wombat1]

Yeah, but moving to another city doesn't fit into my reef budget!! I hear Portland has great water right out of the tap, though. Anyone agree??