Water tank.... overflow

Even if you didnt have an overflow/air flow tube for some weird reason, it would just spit water back out the entrance

Listen closely, and you'll hear a gurgling sound when it's close to being full. At that point I shut the hose down to a trickle to top it off.

If it is a gravity fill type (you stick the hose in a hole to fill it) you will probably have a little vent inside the hole covered with a screen. As the tank gets full you will start getting some water spitting out of the vent. Basically with a gravity fill you can not do it wrong. Provided your hose does not completely block the fill hole. When it is full water will overflow back at you.

If it is the type you actually screw your hose to you will likely have one or two vent hoses under the trailer. These vent the air from the top of the tank. When the tank is full water will start running out of these hoses. You want to pay attention because your pressurized hose can fill the tank faster than the vent hoses can let it out. When water starts coming out the vents turn the water off.

While filling you can have someone in side looking at the gauge to tell you when it's full. Or you can do like most of us do fill till it starts to come out the overflow. You mite purchase a water thief some times the camp ground spigots are not threaded.

Can't over fill it. There is an overflow tube, water will start pouring out that tube. That's the only way to know it's full!

The tank has to have a overflow hose whose real purpose is to let air into the tank as you use water.

For the first time fill very slow (a low pressure regulator would be good) and watch for the overflow. After that you may be able to fill faster.

There are no silly questions posted here just silly answers.

Your question has been asked before. Try to do a search on water overflow

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