Salinity jump about 1-1.5ppt when lights come on?

[110galreef]

Anyone else have this or know how to fix? I have latest firmware......
check probe readings against refractometer properly calibrated as well as a hydrometer.

When lights are on the conductivity goes from like 35ppt to as high as 37ppt.

 

[110galreef]

was plugging along at 35.5 all day long, then from 3:40 to 3:50 (MH's on at 3:15) salinty jumped from 35.5 to 36.6, then usually about 10:10pm (MH off at 9:30) the salinity drops back close to its normal reading over 10min prd. This seems to be the norm everyday at the same times.

Idears??

 

[aquamanic]

Interference?

 

[110galreef]

Apex...is that what u mean?

 

[aquamanic]

??

Interference - something else is generating some EMI that the probe is picking up (they're electronic after all) and it's corrupting the signal. Rerouting cables, moving the probe are easy ways to eliminate that as a possibility.

 

[110galreef]

Doh..interference. I read quick & "saw" interface....hahha.

I have no light cables near the probe cables. The ballast are w/in a few feet of the modules, of which i can move & see if it helps. But if interference from the light why would it be around the time the lights turn on, not exactly? Electrical gremlins are odd creatures!

 

[aquamanic]

These things are often a process of elimination, taking the most likely candidates out of the equation until you find the problem. If its easy enough to move the probes, even if temporarily running the wires outside the tank/stand and on the floor, then you would quickly know if that was the issue or not.

BTW, do you have temp compensation enabled? I'd imagine your tank temp rises while the MH's are on.

 

[110galreef]

The probe wires are ran separetly in a the wall adjacent to the stand. The MH wiring is completly opposite of these wires.

I don't have temp compensation on? however, my temp really doesn't rise when MH's kick on. The heater stll has to run to keep temp steady. Tank in basement. Also this salinity jump happens w/in 10-20 mins of MH's coming on and pretty much is all at once. No other time thru out the day do i have a extreme shift other than about the time the MH's are on & when they go off.

 

[aquamanic]

I'd try temp compensation then. You'll need to put the probe on the PM2 module and it will get a new name.

 

[110galreef]

since every jump seemed to be associated w/ my MH's or acctinics.......I unplugged them from the EB8 and plugged them in a totally separate outlet/circuit. I also moved the ballast as far away from everything as possible. Seemed to solve it. My ballast were about 3.5 feet from probes & about 1.5' from the modules.

So today, i amgoing to leave the ballast as far away from everything as possible, but plugged the lights back into the EB8...i will know in a few hrs......

 

[aquamanic]

Good to know. Interference was my first guess. Even though the probe wires are shielded, there's been some reports of MH ballasts causing problems. If you determine that's it but can't keep the ballasts far enough from the probes on a permanent basis, you could try getting some chokes from Radio Shack and putting them on the probe wires to see if that helps.