Rodi question

[Scotty Fraiser]

If my tds meter starts to read high I think I need to change the di resin. How do I know when the other filters need changed? Rodi unit is 1 year old and doing 15 gallon water changes every two weeks. Have only changed di resin once about a month ago and the tds is already reading 25. Thanks for any help in advance.

[jeffaquarius]

How long ago did you replace the ro filter? A pressure gauge on the filter will drop significantly or the volume of ro/di is too low. Other system have tds on both sides of resin cartridge. You can also take sample of RO for tds.

[Scotty Fraiser]

I replaced the di resin about six weeks ago. I don'thave a pressure gauge but I'm not opposed to getting one.

[jeffaquarius]

The RO filters are the first to get clogged up or used up. If resin is replaced you might as well replace the RO filters too. If your TDS meter does not monitor the input side of DI you need to get a portable TDS meter.

[Scotty Fraiser]

It is a double one. It measures going in and coming out. Lfs told me to just change di resin. But sooner or later the others have to get clogged?

[jeffaquarius]

If the 25 tds is the output then there is a problem. Your RO filter might be overdue. When installing the filter, you need to flush it by letting it run for about 10 gal as waste before hooking up the DI. What is the input tds reading?

[Scotty Fraiser]

The input is reading about 240

[Scotty Fraiser]

Is the ro filter throne on top. The di is the resin? When I read about them I'm never sure which filter they are referring to.

[jeffaquarius]

The top one is the RO membrane while the first 2 hanging are the RO filters which has to be replaced more often like every 6 months depending on how bad your water supply is. The last one hanging is the DI which is the resin you just replaced. If the 240 tds on the input side of DI then you definite need to replace both RO filters and membrane. You should have taken notes on what was the readings when you first installed it.