When do I change the cartridges for my RO/DI unit, + other?s

[faztaz]

I have a 100 GPD 4 stage RO unit. I’ve had it for 3 years now, and usually the water reading is anywhere from 0-5 ppm before I change out the cartridges. When I change the carbon I also change the 5 micron filter as well. The DI resin is changed after every two changes of the other two cartridges. My question is how can I tell which cartridge needs to be replaced. My reading right now is 8 ppm, so how can I tell if I just need to replace just one cartridge or I need all three. Also how long does the RO membrane last. I flush for a good 30 sec – 1 min after every use. I usually fill my tanks with 5 – 15 gallons per use. I plan on getting a 40g storage container so I can use the unit 40g at a time. Any suggestions as to how to prolong the life of the unit and cartridges would be most appreciated. Also what should be my protocol for changing out the cartridges? Thanks and happy new years!
_________________
Myositis Forum

 

[liquid]

One thing you could do is grab this dual TDS meter from Aquarium Water Filters:

In-Line TDS Meter
http://www.aquariumwaterfilters.com/Ins ... s/TDS.html

Plub one after your RO and one after your DI. If you notice your RO TDS starting to climb it probably wouldn't hurt to change your sediment and carbon filter first. If that doesn't resolve it, then replace your RO. Once you see your TDS climbing from your DI it's probably time to change that then.

hth

Shane

 

[reefland]

Agreed. I used the above TDS meter as well.

 

[cdeakle]

Liquid,

Thanks for the advice. I will get one as well!

-puff

 

[liquid]

Agreed. I used the above TDS meter as well.

Used or Use? If "used", why did you quit using it?

Shane

 

[reefland]

I still use it. Typo.

 

[Unresistible Blue]

Don't forget that a TDS meter won't help you determine when to change the sediment filter and carbon filter. These don't affect TDS in the water stream. You need a pressure guage before the RO to monitor when the system pressure drops below your line pressure to know when these filters are plugged, or easier yet, replace them once every 6 months if you're not certain.

Blue

 

[Emperator]

found the exact inline tds meter for much cheaper:

http://reefgeek.com/products/categories ... 03421.html

the cool thing about this inline tds meter is that you can hook it up in two places. i would hook it up before the di and after the di. this way you can tell if your di is in need of change or not.

i will definitely be getting one of these when i get my new ro/di. i currently use a handheld hanna tds meter.