I know this sounds kind of dumb, but I often shower with the plug in, and just scoop the water into the toilet when I'm done. My wife thinks I'm nuts, but it does help with not filling the grey tank so quickly. I do the same with the dishwater sometimes. We have a 197, so we aren't having to walk 50' from the sink to the toilet!
2012 Jay Feather 197 w/pull-out
1997 GMC Sub 1500 4x4;
or 2015 Ford F150 4x4 SuperCrew EB