Black tank flush system

Did any water actually get INTO the tank? If not the check valve at the inlet may be stuck closed and the water never made it past the valve.

On my old Quickie Flush, the hose blew off once at the tank. I put it back on and re-tightened the clamp.

The tank isn't sealed and the piping is much larger than the hose, so you probably can't do any damage.

Did you check the floor of your tt? On ours, when that happened, water also came out from under the bathroom sink.

Stupid question, but are you sure you had a washer installed? I know on my black flush connector, I sometimes have to use two washers in the female connector because the male threads aren't deep enough on some water hoses.

The concern is that you could blow the hose off the flush nozzle. On mine that happened and I had to drop the sealed underbelly then remove and replace the soaked insulation. Fortunately it was fresh water.

Of course a year or two later the same rinser with it's hose now securely clamped onto the inlet caused my black tank to rupture stem to stern. Yep I got to pull the belly again and remove the insulation again, only this time it was a much more foul job.

Unsolicited advice, leave the dump valve open while the rinser is running. :)