exhaustion rate for RODI filters

[stanleo]

Having an argument with my husband. We have been running 40 gallons every two weeks through the RODI for eight months. This is not including the original 120 gallons used to set up the tank and the 50% WC after cycling. Haven't changed the filters yet. I want to get a TDS meter on Amazon for 13 bucks but he keeps asking why we need it cause he doesn't think they would be close to needing changing out and I want to make sure we stay ahead of that. Please help me settle this.

 

[hllb]

My DI cartridge is going really fast. Fwiw, I picked up a TDS meter for cheap on Amazon and it works very well.

 

[Jet915]

I would get it. They are cheap. I seem to go through filters every 6 months...

 

[andrewkw]

Could last a week, could last a year or even more variation. You've given no indication on what your source water quality is.

 

[stanleo]

Thanks guys. He ordered one, he was just being a jerkface. He likes to torment me cause if he didn't reign me in I would empty the bank account on this tank.

 

[ca1ore]

Having a TS meter, ideally one that can measure from a few points, is very useful. Not sure entirely what you meant by ‘filters’? I generally replace the DI prefilters (particulate and carbon) anually; the actual DI membrane once reject rates start to decline (about every 3 years); and the ion exchange resins every few months as the color changes dictate.

 

[PatW]

You can get a tds meter from bulk Reef Supply that will measure your water before it goes into the DI canister and another when it comes out. It has one display which you can switch. It is easy to see how your RO membrane is performing and if your DI is depleted. One of these guys cost $30.

 

[fcmatt]

I can be wrong but if you are going to do it and plan to be in the hobby for a while getting the ability to test 4 different points in the system can save you money! Why change anything on the ro side if tds reads 1 through 6? Knowing what comes out of your tap is key to know if that 1 through 6 is good or not.

To get your money's worth out of di resin you use two containers of it. Test tds out of the first and second. That way you use all the di resin before replacing. Swap the last container to the first position. Fresh in the 2nd.

It also helps in detecting channeling through the di resin. Just give the containers a few whacks and watch it drop from 1 to 0 again.

If this helps you go much longer then before it is saving you money and confidence in your system.