Struggling with salinity sensor

[Wiskey]

I've struggled with my Salinity probe for about 3 years now. Ever since it was new. I've tried grounding the tank, putting the probe in different places, isolating the wire, even putting one of those magnetic shielding things around the wire. Nothing helps. The tank is GFCI protected.

I have an apex classic with the salinity module and probe. It has 2 EB8's, flow module, head unit, lunar simulator, and two of the breakout boxes.

With the lights off, and my return on it reads 33 ppt. A little off, but that's fine.
If the lights come on, the reading will drop to 27 ppt.
If I turn the return off, the reading will tank to 16 ppt.

What can I do? I thought this might be because of stray power but with the tank grounded and GFCI protected if there are any stray power the GFCI should trip.

How should I troubleshoot? Have any of you had an issue like this? How did you fix it?

Whiskey

 

[pdxmonkeyboy]

ok, here is the situation. salinity probes suck..all of them. sabe your money, dip your refracometer to check salinity once a week.
Done..

 

[Reefer Deez]

Have you tried contacting apex to see if it’s just a bad probe? Also what does the probe read when you are calibrating it? If you leave it in the solution does it read correctly?

 

[Wiskey]

ok, here is the situation. salinity probes suck..all of them. sabe your money, dip your refracometer to check salinity once a week.
Done..

I was hoping to use it as an auto topoff failsafe,.. it could be really valuable.

Whiskey

 

[Wiskey]

Have you tried contacting apex to see if it’s just a bad probe? Also what does the probe read when you are calibrating it? If you leave it in the solution does it read correctly?

The probe seems to work okay if it's removed from the aquarium, but I haven't put it in salt water. I only used it to check Kalk saturation levels, and only briefly. Tomorrow I can check it in salt water removed from the aquarium and report back.

Whiskey

 

[pdxmonkeyboy]

I was hoping to use it as an auto topoff failsafe,.. it could be really valuable.

Whiskey

just use a maximum run time for your ATO pump as a failsafe.. by the time your salinity probe dropped.. too late

 

[hybridazn]

If the readings fluctuate that much when you turn things on and off I believe you have your answer. The equipment is causing the fluctuations. Wires must be in close proximity of each other.

I too have a salinity probe that reads off, but it stays consistent. If it drops or rises too fast I know something happened in the tank.

 

[Waters]

I agree, the accuracy of the probes can be questioned, but they normally stay pretty consistent (even if the numbers are off). I play with the temp offset settings once it stabilizes and try to get the readings as close to correct as possible. That being said, it doesn't explain why yours keeps jumping around. The fact that it is changing when the lights go on and off is very strange.....definitely points to an interference from the lights. I actually have my salinity probe zip tied together with roughly 6 other cables and have no issues though........

 

[justingraham]

Correct me as I am probably wrong but doesn’t the module have a temp probe port?
I beleive u have to have a probe in it for it to work I didn’t see anywhere where u said u had one in it

But with it going up and down with different equiptment turning on and off I would say it has electrical interference somewhere mine drops a point when my lights are on

Even if u fix the probe I wouldn’t use it to control anything I would set up an alarm tho

 

[Wiskey]

just use a maximum run time for your ATO pump as a failsafe.. by the time your salinity probe dropped.. too late

I have this as well, but I figured that you can never have too many failsafes.

Whiskey

 

[Wiskey]

If the readings fluctuate that much when you turn things on and off I believe you have your answer. The equipment is causing the fluctuations. Wires must be in close proximity of each other.

I too have a salinity probe that reads off, but it stays consistent. If it drops or rises too fast I know something happened in the tank.

I agree, the accuracy of the probes can be questioned, but they normally stay pretty consistent (even if the numbers are off). I play with the temp offset settings once it stabilizes and try to get the readings as close to correct as possible. That being said, it doesn't explain why yours keeps jumping around. The fact that it is changing when the lights go on and off is very strange.....definitely points to an interference from the lights. I actually have my salinity probe zip tied together with roughly 6 other cables and have no issues though........

I get where you are coming from, but all my other cords stay in the stand, this one goes out the back where it is coiled on the floor then comes back in and goes directly in the sump. It's not perfect, but that's as far from other wires as it can be.

Whiskey

 

[Wiskey]

Correct me as I am probably wrong but doesn’t the module have a temp probe port?
I beleive u have to have a probe in it for it to work I didn’t see anywhere where u said u had one in it

But with it going up and down with different equiptment turning on and off I would say it has electrical interference somewhere mine drops a point when my lights are on

Even if u fix the probe I wouldn’t use it to control anything I would set up an alarm tho

You are correct, it does have a temp port. And I have a temp sensor plugged in there for temp compensation. I was shocked how far off the readings could get without it actually. I think that's why it calibrated a few points off because the calibration solution wasn't at the same temp as the tank.

Whiskey

 

[pdxmonkeyboy]

I have this as well, but I figured that you can never have too many failsafes.

Whiskey

true enough, but for me, i dont want false failsafes. My ph probe is pretty stable but it does move up and down with temp changes.

Sure, its always good to be notified when there is a problem, i was just giving you another failsafe (run time) that would prevent a problem.

cheers

 

[Wiskey]

true enough, but for me, i dont want false failsafes. My ph probe is pretty stable but it does move up and down with temp changes.

Sure, its always good to be notified when there is a problem, i was just giving you another failsafe (run time) that would prevent a problem.

cheers

Fair point, I don't want false failsafe's either. It just makes me panic. I was really hoping there was hope for this salinity probe. Especially since I spent so much money on it,.. If it can't work on the average tank then I wonder why Neptune is selling it.

Whiskey

 

[dragon99]

Does the salinity module connect directly to the head unit or is it chained to something else?

 

[TinyChocobo]

I programmed my Apex with a few profiles for my ATO. One triggers when the ATO is over a certain wattage [pumping water] and the other triggers when the first is running for X minutes - so not only will the ATO kick off with a loud beep [It's a Tunze] but my Apex will email me that it's been running for a long time and is about to alert with a loud annoying beep.

This way I can do two things:
1. Turn off power to the ATO manually via ApexFusion.
2. Investigate it before I'm there in person to hear the beeping in person.

My tank is in my office so it's best if I keep it from beeping loudly and annoyingly if at all possible .

I'm sure I can do a little more programming to turn the pump off and keep it off after alerting me, but haven't messed with it as in this situation I'd want to look into it quickly anyhow.

My salinity probe on my Apex - I've made sure it's cable is isolated and have re-calibrated it a few times - and it still seems to swing / not read accurately - but my refractometer says I'm dead on and consistent.

 

[Wiskey]

Does the salinity module connect directly to the head unit or is it chained to something else?

It's plugged directly in - my EB8's are chained but the salinity module and the first EB8 are plugged right in.

Whiskey

 

[Wiskey]

I programmed my Apex with a few profiles for my ATO. One triggers when the ATO is over a certain wattage [pumping water] and the other triggers when the first is running for X minutes - so not only will the ATO kick off with a loud beep [It's a Tunze] but my Apex will email me that it's been running for a long time and is about to alert with a loud annoying beep.

This way I can do two things:
1. Turn off power to the ATO manually via ApexFusion.
2. Investigate it before I'm there in person to hear the beeping in person.

My tank is in my office so it's best if I keep it from beeping loudly and annoyingly if at all possible .

I'm sure I can do a little more programming to turn the pump off and keep it off after alerting me, but haven't messed with it as in this situation I'd want to look into it quickly anyhow.

My salinity probe on my Apex - I've made sure it's cable is isolated and have re-calibrated it a few times - and it still seems to swing / not read accurately - but my refractometer says I'm dead on and consistent.

Sounds like a great plan. I have mine setup with three sensors. A center one that does most of the work, and a over full one, and a over empty one.

I also have the top off pump setup so that it only runs for 60 seconds every 15 min. This way it would take over 3 days to overflow the sump and since I use kalk I can never have too much of a PH spike.

Still though,... I would love to know my salinity.

Whiskey

 

[Wiskey]

So,.. I think I've come to the conclusion that it's totally impossible for the salinity probe to ever work. Thank you everyone for your help and experience!

Honestly, I'm disappointed in Neptune. I really thought they only made good quality equipment, everything else I have from them is of high quality. I think it's awful that they sell this without warning people that it is not for salinity measurement, and it can't work for that.

Whiskey

 

[Wiskey]

I mean just take a look at this graph from the last couple days. This thing is totally useless:
Salt by Wiskey2727, on Flickr

Whiskey