Salinity fluxuation

[rene9898]

Have a reefer 350 up and running now for 3 years now.

For the last 3 weeks I’ve noticed that the salinity fluctuations every 12 hours from 34 to 37ppt.

I double checked readings with my Hanna and same readings.

I have the oem reservoir and ato. I add RO water to it every 2 days.

Any advice?

 

[EeyoreIsMySpiritAnimal]

First, NOT an emergency.
Second, is your temperature stable?

 

[TheHarold]

Salt doesn’t magically appear or disappear.

This is likely something messing with the probe. Use a proper refractometer before you implement any changes based on probe readings.

 

[Lbrdsoxfan]

Salt doesn’t magically appear or disappear.

This is likely something messing with the probe. Use a proper refractometer before you implement any changes based on probe readings.

This. More than likely electrical interference. Had a similar issue and it was bad T5 fixture grounding. You could set a watch to the salinity numbers dancing around.

 

[rene9898]

First, NOT an emergency.
Second, is your temperature stable?

Sorry thought I removed the emergency icon.

temps are also fluctuating too.

 

[rene9898]

This. More than likely electrical interference. Had a similar issue and it was bad T5 fixture grounding. You could set a watch to the salinity numbers dancing around.

The Apex system I bought in November 2022, it did not come with a salinity probe. The probe is brand new, less than a month.

Everything is wired and managed by my Apex. What I have noticed is all my pumps, heater and lighting are turning off and on, they never did this prior to adding the Apex.

I’ve sent in the Apex in Feb for warranty work and they told me they’ve fix the sitting down problem.

Could the Apex still be a culprit? Or something else.

 

[TheHarold]

Sorry thought I removed the emergency icon.

temps are also fluctuating too.

View attachment 3148935

That is a pretty severe daily temperature swing. You should get a heater, or if you have one, investigate why it performs so poorly.

This much of a temperature swing will cause issues with your salinity probe if temperature compensation is not enabled.

 

[Joseph3]

Electrical conductivity, which is what a salinity probe measures, changes with temperature. A 4 degree swing is not insignificant. Some EC probes can automatically correct based on the temperature the probe measures, but maybe your probe doesn’t or it’s temp sensor may be broken. It might be worth looking into why you are experiencing temperature swings. 79- 75 in 12 hours seems unusual. But to rule out any other possibilities, do you dose anything that could affect the salinity?

 

[Lbrdsoxfan]

The Apex system I bought in November 2022, it did not come with a salinity probe. The probe is brand new, less than a month.

Everything is wired and managed by my Apex. What I have noticed is all my pumps, heater and lighting are turning off and on, they never did this prior to adding the Apex.

I’ve sent in the Apex in Feb for warranty work and they told me they’ve fix the sitting down problem.

Could the Apex still be a culprit? Or something else.

Could be the apex, could be one of your devices. Also as @TheHarold brought up, if you dont have the temp compensation turned on it could cause issues. Imho you have bigger issues with the 4 degree swing during the day, that's a lot.

 

[rene9898]

Electrical conductivity, which is what a salinity probe measures, changes with temperature. A 4 degree swing is not insignificant. Some EC probes can automatically correct based on the temperature the probe measures, but maybe your probe doesn’t or it’s temp sensor may be broken. It might be worth looking into why you are experiencing temperature swings. 79- 75 in 12 hours seems unusual. But to rule out any other possibilities, do you dose anything that could affect the salinity?

Not dosing anything, have two 300watt brs titanium heaters in sump, and a backup 300 watt in tank.

 

[rene9898]

Could be the apex, could be one of your devices. Also as @TheHarold brought up, if you dont have the temp compensation turned on it could cause issues. Imho you have bigger issues with the 4 degree swing during the day, that's a lot.

Where is the temp compensation setting at?

 

[TheHarold]

Not dosing anything, have two 300watt brs titanium heaters in sump, and a backup 300 watt in tank.

I would be surprised if all three heaters failed. It seems more likely you are having trouble setting up heater controller. Are you using the Apex as a heater controller, or the BRS/Inkbird?

Here is a screenshot from one of my tanks with a properly configured (single) heater.

 

[Lbrdsoxfan]

I would be surprised if all three heaters failed. It seems more likely you are having trouble setting up heater controller. Are you using the Apex as a heater controller, or the BRS/Inkbird?

Here is a screenshot from one of my tanks with a properly configured (single) heater.

View attachment 3149043

Nice and tight! My swings are bigger due not running central air and running T5's on both tanks.

Rimless Cube (sps)

Mixed reef (LPS & Softies) w/ canopy

Overlay with salinity

 

[rene9898]

Where is the temp compensation setting at?

I just found the TC settings and it was not active it was at 0.0 so I put it at 2.2 and recalibrated the salinity probe.

 

[rene9898]

I would be surprised if all three heaters failed. It seems more likely you are having trouble setting up heater controller. Are you using the Apex as a heater controller, or the BRS/Inkbird?

Here is a screenshot from one of my tanks with a properly configured (single) heater.

View attachment 3149043

I have 3 spare heaters. Tomorrow morning I’ll swap out the heaters and test the 3 heaters one by one in a 20 gallon tank I’m not using and report back results.

 

[TheHarold]

I have 3 spare heaters. Tomorrow morning I’ll swap out the heaters and test the 3 heaters one by one in a 20 gallon tank I’m not using and report back results.

I think it’s more likely you are using incorrrect controller settings than three heating elements went bed. If you have a 75-79 daily range, the heater should be set to ~78. Then temperature should then not drop below 77.5.

If you have a heater controller that is then plugged into apex and also coded there, it’s possible the two controllers are canceling eachother out. I use the Apex as a high temp cutoff- so heater outlets get “Set On” & “If temp >78.5 then off”.

 

[Morpheosz]

I think it’s more likely you are using incorrrect controller settings than three heating elements went bed. If you have a 75-79 daily range, the heater should be set to ~78. Then temperature should then not drop below 77.5.

If you have a heater controller that is then plugged into apex and also coded there, it’s possible the two controllers are canceling eachother out. I use the Apex as a high temp cutoff- so heater outlets get “Set On” & “If temp >78.5 then off”.

+1 on this, can you post your heater settings from Apex? There's a very clear pattern so it seems like the heaters are being controlled, just with a really big range. It gets a bit tricky with >1 heater to make sure they are not conflicting with each other setting wise.

I have 2 heaters that are each individually capable of handling the tank under most circumstances. I use a BRS / Inkbird controller for one and the Apex for the other. The Inkbird controlled heater does the heavy lifting as I don't want to wear out the switching in my Apex. When all is well, that just manages the temp in a 1 degree range 78-79. The outlet that I have that plugged into simply has code that says if the temp > 80 shut off to prevent any "stuck on" issues. My other heater is a standby and is plugged directly to the Apex and is coded to come on at 77 degrees so it should only come on if the main one is broken or struggling. Occasionally on the coldest winter nights it kicks in for a bit to help the other heater but is otherwise never on.

How big is your tank? If your tank can normally be handled by one heater, then I'd consider a scheme like this. If not, then I'd consider coding 2 of them to the same temp range so they operate as a single "main" heater and the third code to only come on in case the temp drops below that range.

Either way, as others have pointed out, if properly setup, there's no reason for 4 degree temp swings. It is definitely cause for your salinity readings being off, but the temp instability is your bigger problem for the tank, not the salinity.

 

[vetteguy53081]

Have a reefer 350 up and running now for 3 years now.

For the last 3 weeks I’ve noticed that the salinity fluctuations every 12 hours from 34 to 37ppt.

I double checked readings with my Hanna and same readings.

I have the oem reservoir and ato. I add RO water to it every 2 days.

Any advice?

View attachment 3148880

If youre relying on salinity probe, you may be getting false readings. There is a Very High percentile of salinity probe failure with R2R owners (im one of them- 3 probes and none are accurate). I use hanna digital and refractometer to verify my salinity.

 

[Randy Holmes-Farley]

I removed the emergency tag, and the temp compensation of the conductivity is apparently the issue.

Let us know if that stabilizes the reading.