The company that installed this iron filter removed it and gave me a refund. It's been several months since it was removed. No more noisy water heater or calcium buildup in the screens.
Now I am getting reddish brown sediment in the toilet tanks and toilet bowls. The wife is starting to complain about it being hard to clean this stuff off. When I had the water tested several months ago by a local certified water lab there was no iron detected. I bought an iron strip test kit and have been monitoring the water but haven't had a single positive test result. Is it possible there is a small amount present that doesn't register with the test kit but is enough to show up in the water that sits in the toilets?
How do I figure out what kind of iron this is so I can get the appropriate filter?