What is 1000 ppm? Ahh... didn't read far enough. As others said... not to worry on the TDS of saltwater. Check on those nitrates, nitrites and ammonia levels. This is just the first step of a long journey. Enjoy the ride...Getting back into the hobby after being out for 6 years after moving. A lot has changed in the hobby in such a short time. I a, now trying RODI and my output is testing at 2ppm. However two nights ago I set up the aquarium added base rock and live sand. I added my RODI water and salt. Now the is testing at 1000+ ppm. Is that normal? I’ll post specs and pic in the members aquarium section. looking forward to chatting with everyone.