high tds

Hello, I have a 150 GPD water saver RODI unit. It was in storage for 3-4 years while I wasn’t in the hobby. I am now starting again. I replaced both 75 GPD membranes and all filters. I started making water again but can’t get my TDS under 16-18 prior to DI. My source water is 180-190. The...

I currently have a 4 stage filter for my tap water that is 550 TDS. I run through DI resin in about every 2 months for my 25 gallon tank. My tap water is not treated with chloramines. My filter does manage to remove everything so my output is 0 TDS. Lastly, I use the RODI buddy booster pump...