Just bought a SensaTank marine 100. Not installed until next week so I'll update this post with that effort. I liked the fact that it has external sensors, will do three tanks, and the price. Display is a little large but it will work.

I used a snake river tank monitor, super easy to set up, up 4 tanks can be put into the system and list 1/4 1/2 3/4 full.
I found it simple to install and it works GREAT

After a few too many surprises of an unexpected full holding tank, we have the installation of a tank monitor high on our list of winter projects. We like the idea of the systems that use external sensors, rather than internal probes, but we've run into the same problem as Lucky Duck reported below:
[QUOTE=bakerha;8768]
I purchased a tank monitor (external sensors) over the winter and discovered that the tank is built in and surrounded by fiberglass and wood. Any ideas on cutting the tank mount to accommodate the sensors.[/QUOTE]
Harold (or anyone else): were you able to work around the problem of the holding tank being surrounded by a wood enclosure, and if so, how?

The other alternative is a system (like the Dometic) that uses internal probes, but our tank does not have an access port on top, and we're reluctant to cut a hole in an intact tank for this purpose.

Thoughts from anyone who has confronted these installation issues would be much appreciated!

This is on my upgrade list and I have identified which one I would buy, but I have not yet purchased or installed it:

[url]http://ferriellosales.com/Monitoring_Systems.html[/url]

That's the company now run by the guy who built/invented the Snake River system. He's extremely well regarded in terms of customer service, troubleshooting, help, etc, if you look around the web. The system has come well-recommended by nearly everybody I speak with.

I installed the Ferriello - solo panel waste tank monitor and have been very pleased with the system. It was easy to install and the owner (Dennis) actually helped answer a couple questions. I would choose this system again.

I went with the external foil sensors. If I remember correctly, the waste tank sits in a recessed area on the MarkII and I was not able to mount the sensors as far "down" as the instructions called for... I just did the best I could and the monitor has been plenty accurate enough for my purposes.

[QUOTE=StephenK;15569]I installed the Ferriello...
I went with the external foil sensors. If I remember correctly, the waste tank sits in a recessed area on the MarkII and I was not able to mount the sensors as far "down" as the instructions called for... [/QUOTE]
Thanks. The problem we face with our Mark I (I don't know if this is unique to ours, but Harold Baker seemed to have the same problem with his, as indicated in post that I quoted above, from a different thread) is that there is a wood box surrounding the holding tank, making the installation of external sensors difficult. The Ferriello looks promising, but still the same problem, although it offers an alternative which is an internal sensor tube installed through a 1" hole in the top of the tank (which is, I suppose, better than the 3" hole the Dometic system requires). Since the only port in the top of the existing tank is used for the vent, this is still a problem.

[QUOTE=Chachere;15572] The Ferriello looks promising, but still the same problem, although it offers an alternative which is an internal sensor tube installed through a 1" hole in the top of the tank (which is, I suppose, better than the 3" hole the Dometic system requires). Since the only port in the top of the existing tank is used for the vent, this is still a problem.[/QUOTE]

Eeew, cutting another hole in the holding tank is not something I want to do...

[QUOTE=Chachere;15572]Thanks. The problem we face with our Mark I (I don't know if this is unique to ours, but Harold Baker seemed to have the same problem with his, as indicated in post that I quoted above, from a different thread) is that there is a wood box surrounding the holding tank, making the installation of external sensors difficult. The Ferriello looks promising, but still the same problem, although it offers an alternative which is an internal sensor tube installed through a 1" hole in the top of the tank (which is, I suppose, better than the 3" hole the Dometic system requires). Since the only port in the top of the existing tank is used for the vent, this is still a problem.[/QUOTE]

How much room is there between the holding tank and the wood box? How much room is there around the wood box? I have a MkII so not familiar with this installation.

My inclination would be either remove the holding tank, attach the sensor, and re-install (the sensor is pretty thin) or even cut a two-inch-wide slit out of the wooden box.

For those of you with Mk II tanks, the plastic tanks anyway, removal of the tank is not necessary to install the holding tank's foil sensor strips. You just need a paint stirrer to work the foil down the side of the tank.

Interesting suggestions, Larry and David. I'll evaluate these options when I'm on the boat this weekend, but I recall that the space was very tight. And it'll be tricky to cut the box without damaging the tank (maybe a Dremel tool will to it).

Still hoping to hear from another 36 MkI owner who has dealt with this; I doubt I'm the first one to run into this issue....

Matt - I didn't return to this project yet - to many others in the way. But I have a plan to install the sensors. I have a small angle drill and plan to use hole saws with a removable pilot bit. I want to slide a thin piece of brass or aluminum between the wood and tank where the sensors will be installed. Then start four holes along the wood side at the appropriate locations. Once the cutter starts into the wood - remove the bit and finish the holes "very carefully" and install the sensors. Well that's the plan any way. Maybe this spring if my other projects go as planned. Good Luck.

Thanks, Harold.
I was scoping out the possibilities on the boat yesterday, and it looks like I could remove the board entirely on the starboard side of the enclosure box using a Dremel tool with a cutter wheel -- just need to cut the fiberglass that joins it at either end.

Another way might be to cut a slot in the wood box wide enough for the sensors -- looking at a website for the system sold by ferrielo, which is similar, I saw a picture of an installation done that way (different tank, but same problem): [url]http://ferriellosales.com/Testimonials_Page.html[/url]

So, I'm going to go with an external sensor system. Probably won't get to this until the spring, but if I get time to do it before closing up the boat for the winter, I'll post some installation pictures.
- Matthew

I'm considering installation of a tank monitoring system before spring.  Our boat is a C36 1989.  Are there any updates on the options? (Ferrillo, TechEdge/Snake River). 

Namaste (previously Slip Away) has the original holding tank and water tanks.

Thanks!

Ed Budelmann
s/v Namaste C36 Hull# 988 M25 wing keel
18 Highwood Lane
Ipswich, MA 01938-3024

617-818-5544
 

I bought the Sensatank about a year ago.  Install was very straightforward and I'm very happy with it.

I have a bluesea VSM - it can handle several different types of sensors - I have an ultrasonic in the holding tank, normal float switch in the diesel and not sure what is in the fresh water (installed by the PO) - the ultrasonic did require a hole in the top of the tank.-- I think this would be an easier task than installing new hoses on the tank. 

Les