I noticed an air gap at the top of the di resin. I removed the cartridge and slammed it down a few times to pack it and was able to push the filter a half inch or so down. I'm reading 29ppm after the DI now. So there's still some sort of issue with the membrane. Is 29ppm safe for partial water change? Or at least for my ATO?
Ah sometimes if the resin isn't packed tightly and you see it tumbling, this can shorten the lifespan of the resin. Regardless, you shouldn't have as high of a tds for water coming out of the membrane (at least from my experience)