For some reason I don't see your pix..
However..
You are much better off to have the nose slightly DOWN, not level or slightly high.
Reason for this is it shifts the Center of Gravity (COG) FORWARD of the trailer axles slightly and effectively preloads the tongue weight a bit heavier.
Riding tongue up or level effectively pushes the COG BEHIND the trailer axles so when ever you hit a uneven piece of road which makes your hitch ride even higher (like when your vehicle crests the top of a bump but your trailer has not gotten to the part of the road) your trailer now will get unstable.
The key to stability in bumper pulls is to load the tongue to the max, yeah you want 15% tongue weight for best stability.. You didn't have this problem with a 5Vr since they typically have 20%-25% of their weight on the hitch pin..
The other thing that concerns me is you half full tank of fresh water, that is a new stability problem which at the worst time will upset the stability. Having half full tank allows a lot of room for the water to slosh back and forth and side to side.
Depending on tank size that can mean 200 lbs or more of water slamming around.
You want that tank to be completely full or nearly empty, if you do not need 1/2 tank worth of water, then only put a couple of gallon in just for potty breaks and such. 2 gallons of water is 18 lbs of water vs 200+ lbs of water sloshing.
Rather than fixing the level issue with ballast like a liquid it is better to fix it correctly by dropping your hitch lower. IF you cannot drop your hitch to a lower hole on the shank then it is best to purchase a longer hitch shank for more drop.