I know this post is a few months old - I too am thinking about a tank monitoring system. From what I can tell, there are 3 different approaches to automated systems.
Hart Tank Tender The Tank Tender - by Hart Systems, Inc.
uses plastic tubing to measure the fluid level via air pressure in the tank. This approach requires drilling a small hole in each tank, screwing a threaded adapter/nipple/o-ring into the top of the tank and routing plastic tubing to the gauge. There's a concern about keeping the level of the tubing above the tank, to avoid siphon. I've been told that if using in a holding tank
, the tube needs to be cleaned or replaced every 4 years. Prices start at $400.
New Providence Marine
that measures electrical
capacity between 2 aluminum
strips attached to the outside of the tank. This only works on plastic or fiberglass
tanks. They also have tube inserts for aluminum
tanks. Seems like a clever idea and customer support is amazing (I emailed Dennis and received a return phone
call 5 minutes later!). Prices start at $140 for single tank and $300 for 8 tank system.
Blue Sea Systems
has a monitoring system that uses ultrasound sensors mounted to the top of the tank. These require mounting the sensor. Prices start at $340, with sensors around $70. One of the advantages of this is the system also monitors battery amps consumed.
100. Like the New Providence Marine, this device attaches 4 pads on the outside of the tank. These measure 1/4, 1/2, 3/4, Full, based on the fluid level. Prices are around $250.
I'm sure there are other models. I believe I read an Practical Sailor article that recommends the New Providence Marine/Ferriello system for single tank and SensaTank Marine 100 for multiple tanks. Everyone seems to love the Hart Tank Tender, though it is more expensive. I'm impressed with the customer support and following that Dennis Ferriello has developed. I'm split because I like the idea of measuring battery usage and feel that the Blue Sea system is more flexible.
continues - any thoughts or experiences with any/all of these?