Water Tank Metering Project

Bella Star holds 90 gallons of water in two tanks. There are many options available to monitor the tank levels in the water, fuel, and holding tanks. These range from systems that use electrical resistance to systems that use air pressure or internal floats to Gage fluid levels. The accuracy of these systems vary and the speed at which the gauge moves from full to empty is often not constant since most tanks on boats have irregular shapes.

For now, I'm really only interested in monitoring the water tank levels. Our holding tank makes disturbing gurgling noises when it's getting full so no need to put a gauge on that. Our fuel tank is about 80 gallons and I monitor approximate usage with the hour meter. (We only used 16 gallons last season with regular use of the boat so I'm not too worried about running out of diesel.) As for water, rather than monitor the water left in the tank I'm going to monitor the water going out of it. I bought a low flow water meter from http://www.jerman.com/ (DLJSJ50C) that measures down the the hundredth of a gallon. I talked to these guys on the phone about my particular application and they were very helpful in choosing the right meter.

The meter will be attached on the pressure side of the water pumps and is able to output to an LCD display that reads off the gallons used in 1 gallon increments. The LCD display resets to zero by pushing the reset button. So my plan is to get it all hooked up, fill up the tanks, and then pump them dry to see exactly how much we water we hold. Once I've got that number I can just subtract the amount displayed on the LCD to know how much water remains in the tank. Whenever we refill the tank we just zero out the LCD. The meter gets the power to send the signal from a 10-year battery inside the LCD unit. Total cost was about $150.

You can buy a system similar to this (https://birdoff.com/watercounter.php) that is a bit cooler since the readout can be programmed with your maximum tankage and the and readout counts down to zero from a full tank. I decided not to go with this since it required wiring 12v power and it was twice as expensive.

Stay tuned to see how the installation goes and get a report on how it works out!