Gary,

Congratulations on the working filter! Just think what is NOT in your
pond any more!

I suspect most folks have a similar experience cleaning out the
filters. Our berm ponds collect the muck and can be drained through
2" bottom drains by opening a valve. Easy work. We then flush with
pond water. Our upflow barrels are similar. Valves to drain and
flush the strapping tape with pond water.

Folks with screening as the filter medium have to pull it out and wash
it. Easier than blue mats.

Does your barrel drain at the bottom? You might end up with screen to
filter and drain to empty.

Keep us posted on the cleaning rate.

Jim