I did a water heater flush by turning off my heat down to the pilot light only and setting it to pilot instead of on, let it sit overnight. I then opened the stock drain valve and let it drain until it was just trickling a tiny bit. The trickling went on for hours it seems and didn’t stop after approximately two hours that I waited. Almost no sediment came out except for a small 4mm chunk. This doesn’t seem right for a water heater that hasn’t been flushed in about 7 or 8 years if not 9 years when it was first installed. Does a slow trickle plus very little sediment mean there is a big chunk that won’t come out? It was flushing at a really fast rate for a while, to where the hose was being almost fully utilized. I stuck a wire up the drain valve after removing the twist part, but it didn’t cause any more sediment to come out, and it didn’t feel like there was anything blocking it.
The pic shows the sediment after it broke apart when I picked it up.