RO/DI Question

tbrown · Jul 13, 2023

So I have a couple of under sink RO systems in my garage not being used currently. Is there any reason not to add a DI cartridge (or 2) and use these for my reef tank? I know I'll need to replace the filters and membrane first, but there shouldn't be any reason not to use an undersink system, correct?

Uncle99 · Jul 13, 2023

I do this.

Just added a refillable cartridge for DI.

If you can get say 5-10 tds out of the pre DI filtration, that works fine. Much higher would use expensive resin too fast.

The_Paradox · Jul 13, 2023

Will work albeit probably a little slow as the under sink units are low GPD. In all honestly you probably no not even need to add the DI portion depending on your water.

tbrown · Jul 13, 2023

The_Paradox said:
Will work albeit probably a little slow as the under sink units are low GPD. In all honestly you probably no not even need to add the DI portion depending on your water.

We've got pretty hard water out here - 10+ dKh due to high calcium and magnesium levels. I'm not sure on the TDS, I need to get a meter.