Just ordered a Pm2, break out box, 3 horizontal float switches, and a temp probe. Gunna set up my apex to auto fill my ro/di reservoir. Also gunna add a float switch in my saltwater bin. That way if it's ever empty, my auto water change will shut down. Also gunna use the apex to monitor temp inside my saltwater bin. That way if it's ever too hot/cold, I can stop my water change until temp is corrected.