ground probes whats your thoughts?

im worried about my fish, i haven't noticed any change in them since adding the ground probe to the baseboard. as i said all electrical items are in the sump as is the ground probe. I'm hoping its taking any thing out before the water heads up to the display tank

 

If you are reading 120V AC in your sump you have a serious problem.

Are you using a digital or analog voltmeter? When you check the voltage are you connecting the red wire to your sump water and the black wire to a true ground and not your outlet ground since you determined it is not truly grounded?

When set to 50VAC, the meter will max out and not read voltages above 50V. If you have a digital meter, they usually display “OL” when they are maxed out. Is this what you mean when you say “no reading on volts at 10 or 50 but a reading at 250” ?

Try this. With all the pumps on and ground probe out of the sump, measure the voltage between your sump water and the ground probe assuming you have it connected to your plumbing. What did you read?

With all the pumps unplugged, try the same. What did you read?

Now turn all the pumps back on but remove the temp, salinity and Ph probes and remove any refugium light if you have one. What did you read?

What brand of pumps do you have in the sump? There was a problem with current leaks in some very old Korilla 2 and 3s.

 

no they don't max out the meter reads like there is no volts, its a analog meter/ craftsmen has all different settings on it vac actually can read at 1000 volts. anyway i get no reading till i put it on the 250 setting. than the needle moves up.
but when tested in an outlet the volt meter reads as it should ( it pegs at 10 or 50) . thats whats so odd.

i will try what you suggest and get back with readings

my pumps are
2 sicce 1.5's 357 gph
1 in the scw 120 cone skimmer...dont know what brand that is
1 mag 1800 ( main pump)

 

TritonsGarden i did what you said, i found with all pumps powered off, but plugged into the apex. i still got that high 110 or 120 the needle was around there, reading. while testing each pump and probes, i figured let me test without the surge protector... here is something odd, i have a surge protector plugged into the gfi outlet. i removed the surge protector and plugged right into the gfi outlet and retested, and readings dropped to 0 with all plugs plugged in but powered off ...with each pump i turned back on the volt meter read a bit more but did not go past the 25-30 mark in the end with all powered on. i put my finger in the tank to see if i got a shock with the ground probe still out and i didn't feel anything but water.
it seems each piece powered on throws a small amount of voltage into the water which adds up in the end to 25-30 but with a WORKING ground protector in the water the reading is zero.

oh with surge protector removed i also seen the 50 on the meter working.


im guessing we found the problem why would a surge protector do that? your way of testing with the grounded wire made testing much easier for one person to do. thank you so much

as you and rick said the only way to find the problem is to isolate each item and keep testing. that testing and getting a reading when the apex had power off to all and still getting a reading made me look to the outlet.

Thank you rickm and tritons garden for leading me the right direction in finding the problem

 

i did plug the surge protector back in and retest and i got that high reading again. unplug retest reading drops drastically again. i figured i better be sure this is the problem

 

A surge protector works by diverting excess voltage to ground or at least I think that is how they work. Since your ground is not a true ground, it may have been causing some issues. Turning on each pump raises the voltage is consistent with what I see and believe to be induced voltage from the electro magentic fields.

I think you have found the root of your voltage problem. Toss the surge protector or have an electrician connect a true ground to your outlet.

You still need to decide for yourself if a ground probe is useful or not

 

since i have been running the tank without a working ground probe, thinking it was working. i will see if there are changes in fish or corals with a working one, and go from there. honestly I'm still confused by ground probes ...i see they do lower volts to 0 but i still don't know whats best. and wonder if it does create current in the tank? and if so if there is current why a 0 reading to me a 0 reading would mean there is no current ??????? so many questions ;D
i added the GP for safety. mine and the fishes. i thought it was working. should have tested it from the start i guess. i will also test with the probe out from time to time to be sure readings on the meter stay the same.


thanks again for all your help. i was pretty stressed by the shocks and readings

 

Glad you were able to figure it out, electricity scares me

 

Thanks, and thank you for your help, and i believe your teasing me about it scaring you