Ro water quality is bad

olavvk · Jan 15, 2022

I have an easy line 300 osmosis ( RO) filter. I have used the device once, so it was bought new and I now measure a value of 25ppm, the normal tap water from the tap is 425 ppm. what can I do to get my osmosis water to 0ppm? And what would be the risk if i use this water?

Mr. Mojo Rising · Jan 15, 2022

I just googled it, it doesnt seem to have a DI cartridge, if you can add a DI cartridge it might help bring the TDS down to 0.

Bato367 · Jan 15, 2022

If your filtration system consists of only an RO membrane, you will need to install or add on additional filters.

Most RO/DI systems, say with a "4 stage" RO/DI, the water first is filtered by the sediment filter, then carbon filter, then to the RO membrane and finally through the DI resin filter then to your RODI water storage.

If you have all of these and still can't get 0 TDS, then either your filters need replaced OR your source water is dirty enough that you need additional filter units.

Without pre-filtering the incoming water, the RO membrane likely won't last long at all. It is doing the work of 3 other filters.

olavvk · Jan 15, 2022

Thanks for the answers! So i have 3 now, sediment filter, carbon filter and the membram. So if i buy a di resin filter, i just can connect it to my RO membram filter?

olavvk · Jan 15, 2022

Bato367 said:
If your filtration system consists of only an RO membrane, you will need to install or add on additional filters.

Most RO/DI systems, say with a "4 stage" RO/DI, the water first is filtered by the sediment filter, then carbon filter, then to the RO membrane and finally through the DI resin filter then to your RODI water storage.

If you have all of these and still can't get 0 TDS, then either your filters need replaced OR your source water is dirty enough that you need additional filter units.

Without pre-filtering the incoming water, the RO membrane likely won't last long at all. It is doing the work of 3 other filters.

So this is the di resin filter right? If yes, i will try this to add at the final stage of my osmosis filter

Bato367 · Jan 15, 2022

olavvk said:
So this is the di resin filter right? If yes, i will try this to add at the final stage of my osmosis filter

Looks like it should work. And no, I would not use that 25 TDS water...It would only cause headaches.

aquaman67 · Jan 15, 2022

An RO membrane is a mechanical filter. Meaning it strains out molecules that are larger than water molecules. About 95% of what’s in your was removed by your RO.

Some molecules are smaller than water molecules and will pass through an RO membrane. (That’s why your water after the RO is still 25.)

So, to get all of the molecules out of the water you will need to use a deionizer. A deionizer uses the electrical charge of molecules to remove them.

The reason you need to use a deionizer is because one of the molecules that is smaller than a water molecule is phosphate. (Many municipal water systems add a type of phosphate to control scale in water mains)