I also want to add a note for people that have Ultimas. I do a backwash when I’m changing the water every week. But I reread the owners manual and noticed it says to perform a proper backwash, you should back was for 30 seconds, then rinse for 1 minute, then back wash for 30 seconds then rinse for 1 minute, until you don’t see anymore waste come out of the outlet anymore. I had been just putting the filter in backwash and letting it run for about 10 minutes until the water level dropped in the tank to about 50%