Look for your manual for the toilet. It should show how to remove the valve located on the back of the toilet without having to remove the toilet. Before removing the valve ensure you shut off your connection to city water and/or turn off your water pump. Then open one of your bathroom sink faucets to remove pressure from the water lines. There should be a small screen in the valve that is easily clogged by debris. Once cleaned, reinstall the valve and check the water flow. It should now be OK. Then check the anode rod in your water heater. As the anode rod deteriorates, the particles travel in the water system and begin to clog faucets, etc. For some reason the toilet valve seems to be one of the first valves to clog even though it is served by cold not hot water lines. Go figure!
If your anode rod has deteriorated, you should replace it after thoroughly flushing out your water heater tank, which is very easy to do.. Search “anode" on this forum for more information. Hope this helps solve your problem.
John & Gloria Hunsaker FROG Member CA-0030-988
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