I have a 2020 Magnitude SV34, and like Judge, I did not like the hassle of dismantling the bed to fill/drain fresh water, but because I am in a northern climate I was afraid of having an exposed water valve. I purchased this stainless steel valve (for potable water) on Amazon:
U.S. Solid Motorized Ball Valve- 1” Stainless Steel Electrical Ball Valve with Full Port, 9-24 V AC/DC, 3 Wire Setup
I wired it to a SPDT (single pole double throw) switch to my 12 volt system (you could also use a 9volt battery). I "hid" the switch under the bed to keep my young grandson who loves switches from accidentally dumping my water!