Frequently Asked Questions

How do I install the Horst Miracle Gauge?

Be sure to watch our installation video or print out instructions here.

How do I operate the Horst Miracle Gauge?

    1. Select the tank by rotating the knob
    2. Fully depress the knob and hold
    3. Read the depth of the tank in inches
    4. Slowly release
    5. Wait a few seconds between readings

Be sure to watch our short video demonstration here.

Where is the best place to install the Horst Miracle Gauge?

The best place to install is in the bathroom, which is where other plumbing fixtures are located, and therefore close to all 3 tanks. Follow the path of electrical wires down to the tanks.

The tank may be as far as 30 ft away from the location of the monitor.

How do I learn about the volume in each tank at any tank level?

The Horst Miracle Gauge measures the height of the fluid level in inches, starting from where the connection is made. Because of this, it is important to have a connection at the lowest point possible, and to learn the volume in your tank. This is so you know what 1- inch of water level in your tank means in gallons.

If you know you have a 10-inch tank that holds 25 gallons, you’ll know that a 5-inch reading means that your tank is half full and that you have 12.5 gallons of water in it (provided you are not parked on a slope and that you have the connection at the lowest possible point).

Tank capacity information may be found in your rig’s literature. Most tanks are between 6 and 10 inches high.

If this information is not available, you can fill up 5-gallon buckets of water, and dump that into your toilet or sink, and take a reading for every 5 gallons you’ve added until you have completely filled up your tanks. (If there is a sudden spike on the gauge, you are past maximum capacity and you are completely full.)

You can also can fill the tank up with a hose, and let 5 gallons of water out at a time, while making a note of the gauge readings. This works well with the fresh water tank.

Another way to figure this out is if you know how many gallons come out of the hose in a minute (such as 5 gallons / minute). In this instance, you can see what each minute translates to on your gauge.

Can I buy extra tubing?

Yes. The Horst Miracle Gauge already comes with 37 feet of tubing. If you would like to purchase an additional 37 feet, you can do so here.

Do you have an option for a 4-Tank system?

Yes. You can purchase a Horst Miracle Gauge for a 4-Tank System here

Is there a risk of mixing of fluids or gasses between the black and fresh tanks?

In a stationary condition on “fresh” there is a closed circuit connection from the black long line groove on the push button to the fresh water level.   No contamination possible.  Air flow is in one direction only when pushing the button, air is in stationary position normally.

What if the tubes get clogged?

Tubes have never clogged on me and if so, just take the tube off the actuator and with an airblow gun blow out any obstruction. You will never have to crawl under the RV to the tanks again. 

What, if any, is the effect of altitude on the depth measurement of this system? I often camp at altitudes of 7,500 feet and greater. Will I find some discrepancy in the readings due to the higher elevation?

There is no effect whatsoever. The weight of water stays the same.

I am wondering about the use of your system in my boat’s black water tank.  Our system uses a vacuum flush system and I wondered if the system would still work in this situation.

It would be fine to use it as long as the selection knob is not in the black tank position while flushing. It could damage the gauge. Any other position even in-between positions would be fine. We normally recommend putting the selection knob in the center position. The pressure gauge is not designed for negative pressures/vacuums. 

I have no idea how we’re supposed to get the tubes up inside the interior wall. Can you advise?

The reason we recommend installing the gauge in the bathroom is because of the large number of openings between the main floor and the basement.  Think of joining electrical wires of switches, outlets, drainpipes inside the bathroom, but also from rooms on the other side of the wall.  Try to find a spot above the electrical wire distribution center or otherwise go down with the tube inside a closet.  Go down, use gravity, don’t try to come up.

I push the buttons and the gauge doesn’t hold but drops as I hold. Is this normal? 

The gauge measures the air pressure that is under the push button and in the vinyl tubing to the tank. The total volume of the compressed air is less than 1 cubic inch.  Even the very smallest amount of air leakage (which is normal) will decrease the pressure shown on the gauge. Because of this, you have to read the level immediately after the needle has come down and stabilizes before it goes down to zero. 

I only have a Fresh Water tank in my camper. Do I have to somehow cap off the other two options for black and gray water if not attached to anything?

There is no need to cap off the other options. You can choose any of the 3 positions.Is there any reason why the gauge can’t be mounted horizontally? Or does it need to be standing vertically to work properly? 

Is there any reason why the gauge can’t be mounted horizontally? Or does it need to be standing vertically to work properly? 

That shouldn’t be a problem as long as the lines (tubing) go down immediately.