Originally Posted by Eric F.
You may just have a tower of doom blocking the drain. I have a forty five degree elbow with a hose hook up to shoot a jet of water back into the tank. Backfilling the tank may break up the blockage and allow everything to drain out.
Sorry if that is a little to graphic.
The trouble with the "back flush" method is that once the drain valve is partially blocked, the incoming water from the hose pressure has no force. By the time it turns the corner at the valve and gets into the tank; it just can't break anything up.
It is more effective to use a turboflush or toilet wand and work from the top.
The best way is to use bacteria and enzymes over time to eat away at that mess; then turboflush or wand the tank.
Always use a clear elbow in order to look for clear running water when turboflushing and don't worry if it suddenly stops. Keep flushing because when a clump hits the valve body water needs to build up a back pressure to push out the TP/solid that has been knocked loose.
Professionals will use a special wand on a pressure washer to get in there and blast stuff loose. If that does not work, tank replacement is the last resort.
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