Just upgraded to another 100gpd in parallel with the existing one, and tds has shot up to 035 after 2 x DI units, swapped them over and its gone down to 011, so really need to change the resin. Having never done this before I've taken the containers apart and emptied the resin out. I'm now left with four dirty/soiled foam filters and some sediment left in the container.
How do you wash these, just with tap water or pure water to stop any impurities, and roughly how much do you re-fill with new resin on a 700ml unit (I have 2)
thanks
Fieldsy