Holding Tank Monitor

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Osprey69

Senior Member
Joined
Jan 12, 2021
Messages
459
Vessel Name
Rogue
Vessel Make
Gulfstar 49 MY
Installing a new tholding ank that has one side exposed to view. Peggy suggested the Scad monitoring system. Great product, but trying to avoid wiring up anything.

Site glass will probably foul. Or not? Other thoughts?

Thanks in advance.
 
site glass will 100% foul... Think about what "goo" you will have floating in there!!! Depending on how long you can wait, I spoke w/ the owner of Scad a while back (2-3 months ago) and he mentioned working/looking into a N2K version of their current device... So you would be able to connect that into your N2K network and get the tank displays.
Another option is Maretron, still gotta run cables, but N2K cables aren't too terrible to run and connect.
 
When it's empty it may be empty :rofl::rofl:

When it won't hold any more it may be full :angel::angel:
 
If its a plastic tank and easily accessed, holding a flashlight along the back side of the tank lets you easily see the level in the tank. Works great in my application.
 
I have tried several "sonic" units and they all fail as gunk loads up the walls of thew holding tank.

Switched to a KUS holding tank level sensor and a gauge.

Works perfect.
 
Another option would be a tank tender. This just uses the weight of the water so no electronics. Might be an option.
 
site glass will 100% foul... Think about what "goo" you will have floating in there!!! Depending on how long you can wait, I spoke w/ the owner of Scad a while back (2-3 months ago) and he mentioned working/looking into a N2K version of their current device... So you would be able to connect that into your N2K network and get the tank displays.
Another option is Maretron, still gotta run cables, but N2K cables aren't too terrible to run and connect.

You can buy the external (non fouling) sensor that Scad uses for about $40 directly from the people that make it (tankedge.com). I hooked this directly to a Victron Cherbo with the 140 tank sensor, seems to work pretty well. You can get this forwarded to N2K as well.
 
I have a tank tender for my holding tank that was failed before I bought the boat. Shining a flashlight through the plastic tank clearly shows the level and the rate of fill is slow enough for pump out every 7-10 days.
 
Another option would be a tank tender. This just uses the weight of the water so no electronics. Might be an option.



I have used the tank tender on a previous boat and found the tube in the holding tank to clog often. I ended up blowing it out with compressed air
 
DDW-
Can you explain that a bit more? I found the sensors, but not sure about the "140". Do you need the Cerbo to read it? Or could that data be connected/sent directly with the "140" to the N2K network? Looking at the 140, I didn't see any N2K connection points...

Very interested in this, especially if I don't need the Cerbo to make it happen. I have everything else running w/ Maretron gear. But wasn't too impressed with the reviews on their stuff for holding tanks... :(
 
You can buy the external (non fouling) sensor that Scad uses for about $40 directly from the people that make it (tankedge.com). I hooked this directly to a Victron Cherbo with the 140 tank sensor, seems to work pretty well. You can get this forwarded to N2K as well.

When I recently installed my KUS gauge I seriously thought about connecting it to my Victron Cerbo, and then use the relay outputs to trigger the waste treatment system.

My only challenge, and the driver for using the stand alone analog gauge was that I could not get the CERBO to display the tank level on the main graphics display.
 
I am using tank tender on one vessel, now for about three years, have port and starboard water, fuel, and black water on one panel, like it enough I am considering retrofitting another boat.
 
I have had good luck so far using tank tender for the last 3 years. I have had one down tube plug but other than that it is great. Use it for diesel, fresh water too.
 
Installing a new tholding ank that has one side exposed to view. Peggy suggested the Scad monitoring system. Great product, but trying to avoid wiring up anything.

Site glass will probably foul. Or not? Other thoughts?

Thanks in advance.

Why would sight glasses foul (unless your tank is full of crud which will need access port and proper cleaning anyway)?
Guess I’m biased since I have them on all 4 tanks and both water tanks also. Pretty simple & effective. Actually mine are just food grade, 1/2” tubing, no actual glass. Best practice is to close the lower valve unless checking fuel level - sometimes I remember.
 
DDW-
Can you explain that a bit more? I found the sensors, but not sure about the "140". Do you need the Cerbo to read it? Or could that data be connected/sent directly with the "140" to the N2K network? Looking at the 140, I didn't see any N2K connection points...

Very interested in this, especially if I don't need the Cerbo to make it happen. I have everything else running w/ Maretron gear. But wasn't too impressed with the reviews on their stuff for holding tanks... :(
Not a good fit unless you already have Victron in the house or are headed that way. The Cerbo works great with other Victron equipment (inverter/chargers, solar, battery monitor, etc.). I can also monitor my boat from 2000 miles away. But it is sort of an ecosystem you have to buy into. The GX Tank 140 is an accessory that plugs into the Cerbo (or I think any Venus OS device) and has a set of I/O including tank inputs. The Cherbo will also put this on N2K.

The TankEdge capacitative gage is an oddball, putting out somewhere around 0 - 4V, depending on length of the foil, spacing, thickness of tank, etc. Most gages are resistive, some are 4-20ma gages, a few are a voltage source. The GX140 will read this and can be calibrated for the installation. If you want to go directly from the TankEdge to N2K, you need a gage interface that has the ability to read a voltage source gage, that can be calibrated for the 0-4V range, and also supply 10-12V regulated power signal.

The reason to use the TankEdge is it seems to one of very few sending units that will not foul in a holding tank, being outside of and not in contact with the contents. And it is inexpensive.
 
Using a flashlight to examine fluid level in a plastic waste tank is ok until you end up on a boat with tanks that have not been regularly flushed. Hard to see through coated tanks. I have the WEMA/KUS style float-on-a-stainless tube arrangement, and it reads out on an analog gauge in the head. I have no illusions about its capacity to get fouled if the tank is not regularly well flushed. For now, it's been 100% reliable. I have been shipmates with the SCAD and watched as the boat owner was briefed by the installer only to have it misbehave with false data once I got underway for the delivery. I had to reinitialized it a time or two and never trusted it for the next 30 days. Cannot say I'd care for sight gauge on this system unless it had an easily connected blow-down system.
 
Bought the SCAD with the external strip. New tank so should be able to calibrate accurately. Thank you Head Mistress and other posters.
 
Why would sight glasses foul (unless your tank is full of crud which will need access port and proper cleaning anyway)?
Guess I’m biased since I have them on all 4 tanks and both water tanks also. Pretty simple & effective. Actually mine are just food grade, 1/2” tubing, no actual glass. Best practice is to close the lower valve unless checking fuel level - sometimes I remember.


You may have missed it, but the OP is talking about his black waste holding tank.
 
Bought the SCAD with the external strip. New tank so should be able to calibrate accurately. Thank you Head Mistress and other posters.


Good system. I installed one a couple years ago.
 
Dhays-many thanks. Of course you are correct, somehow I transposed this holding tank thread with another on fuel tanks. My bad-sight glasses are of course ridiculous!
 
Installed SCAD system last year with solid fiberglass tanks and cannot calibrate it.
Admiral tried and thank God she couldn't figure it out either. Called tech support and they tried to talk us through it and does not work at all. We're both college grads and full time liveaboards, we maintain every system on our boat and this is a true waste of money
I have a running $50 bet with anyone that can make it work, so far 6 have tried and I still have my money!
 
Installed SCAD system last year with solid fiberglass tanks and cannot calibrate it.
Admiral tried and thank God she couldn't figure it out either. Called tech support and they tried to talk us through it and does not work at all. We're both college grads and full time liveaboards, we maintain every system on our boat and this is a true waste of money
I have a running $50 bet with anyone that can make it work, so far 6 have tried and I still have my money!


Sorry to hear that. I'm curious what the shape of the is and if there are any metal tank fittings near the strips?
 
They can be a pain to program the first time around.

What is the sensor light located at the holding tank doing?

Do you know what the parameters are that you programmed in?

When in doubt go in to program mode on the display and video the settings as it steps though them.
 
SCAD monitors

To answer a few replies I received.
No metal fittings, 3/4 solid fiberglass tanks (Hatteras) one is triangular shaped and we tried to program for that. The other is rectangular and we tried to program for that.
After numerous and I mean numerous attempts we are going to a different product yet undecided. The good thing is we have wiring where we need it!
We have decided that we will put in another system and try to get one system that can handle the water tanks, fuel tanks and waste tanks even though there might be multiple panels to make it easier to wire.
Thanks for the help folks, I just wanted to offer our experience with the product.
I'm glad it works for some.
 
As in 3/4" thick fiberglass? Yeah, I doubt that would work with a Scad type sensor. Or any external sensor.
 
You can buy the external (non fouling) sensor that Scad uses for about $40 directly from the people that make it (tankedge.com). I hooked this directly to a Victron Cherbo with the 140 tank sensor, seems to work pretty well. You can get this forwarded to N2K as well.



Somehow I’ve missed that all along. Thanks. Already have the Cerbo, just ordered the sensor.
 
I used a Sierra Tankwatch on the aluminum waste tank on my Island Packet that worked very well for us. It was a simple float switch with a red indicator light when the tank was approaching full (no 1/4, 1/2, 3/4, etc.). We didn't really need to know exactly what the level was as we almost always had a weekly pumpout, but because we had an electric fresh, pressure water toilet I wanted to make sure that we didn't inadvertently overfill/overpressure the tank or lines.

I mounted the sensor in the top of the tank and the indicator light in the aft head (which had a manual Jabsco). Our forward head had a Raritan electric fresh water and I was able to wire in the Tankwatch switch using a relay to switch the + / - so it would illuminate the "Full" light on the Raritan control switch and disable the head when the tank was almost full.

Simple and effective and we had no issues with the system for seven years and as far as I know it's still going strong (it was when we sold the boat).

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Not a good fit unless you already have Victron in the house or are headed that way. The Cerbo works great with other Victron equipment (inverter/chargers, solar, battery monitor, etc.). I can also monitor my boat from 2000 miles away. But it is sort of an ecosystem you have to buy into. The GX Tank 140 is an accessory that plugs into the Cerbo (or I think any Venus OS device) and has a set of I/O including tank inputs. The Cherbo will also put this on N2K.

The TankEdge capacitative gage is an oddball, putting out somewhere around 0 - 4V, depending on length of the foil, spacing, thickness of tank, etc. Most gages are resistive, some are 4-20ma gages, a few are a voltage source. The GX140 will read this and can be calibrated for the installation. If you want to go directly from the TankEdge to N2K, you need a gage interface that has the ability to read a voltage source gage, that can be calibrated for the 0-4V range, and also supply 10-12V regulated power signal.

The reason to use the TankEdge is it seems to one of very few sending units that will not foul in a holding tank, being outside of and not in contact with the contents. And it is inexpensive.

DDW-
Thanks for the details! I am 100% switching to Victron, the day my Magnum goes up in smoke. While I do like it and functionality-wise it has done very well, I just don't feel like Magnum is putting in the R&D money for the next-gen equipment.
A couple months into Covid I called and spoke with a great tech, their customer service IS TOPS in my opinion (spent almost 2 hours on a call with me)... I was really trying to dig in deep with them about whats coming out, software/hardware upgrades, specifically to put the device on the N2K network. They said they were looking into it, but when Covid hit, all those plans were shelved... :(
That being said, I really like the forward thinking Victron has put into their gear and what they have and are also bringing to the market... Solid gear that can be expanded upon...
 
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