I have been struggling to figure out what's causing my ph monitor to move around and saw this weekend when my 1st set of lights came on my ph readings dropped from 7.97-7.60. I know this is a false reading and when all my lights are on it hangs around 7.57. When lights go off its back at 7.91-7.97. All these reading are from 11:00am-8:00pm. I understand the laws of electricity and didn't know if I should just leave it alone or not. I run 6 T5 HO on my 58gal.
ground prove or no ground probe
- Thread starter bgraves
- Start date
unstopable
New member
ground prob never had any problems
voltage readings.
44v ac with everything on ph 7.37
55mv ac with probe in 7.08
36v ac w/o probe and lights out 7.97 ph
I turned every thing off and on one at a time. The lights make a big difference on the probe readings. I just calibrated 6/15. so I should leave the ground probe in? One of my nems shrivled up and has been for 2 days. I fed them a piece of fresh shrimp. Didn't think that would be an issue how ever the voltage may be.
44v ac with everything on ph 7.37
55mv ac with probe in 7.08
36v ac w/o probe and lights out 7.97 ph
I turned every thing off and on one at a time. The lights make a big difference on the probe readings. I just calibrated 6/15. so I should leave the ground probe in? One of my nems shrivled up and has been for 2 days. I fed them a piece of fresh shrimp. Didn't think that would be an issue how ever the voltage may be.
gabbagabbawill
In Memoriam
Any negative issues you have read are most likely false.
Use the ground probe.
See my post here about it: http://www.reefcentral.com/forums/showthread.php?s=&postid=15142593#post15142593
Use the ground probe.
See my post here about it: http://www.reefcentral.com/forums/showthread.php?s=&postid=15142593#post15142593
gabbagabbawill
In Memoriam
Also, try this:
1. Calibrate your pH monitor with EVERTYHING turned off and unplugged except the pH monitor. Then add the ground plug. Does the reading change? If so, then re-calibrate the pH monitor with the ground plug in place.
2. Plug everything else in and turn it on. You should now see zero change on your pH monitor.
1. Calibrate your pH monitor with EVERTYHING turned off and unplugged except the pH monitor. Then add the ground plug. Does the reading change? If so, then re-calibrate the pH monitor with the ground plug in place.
2. Plug everything else in and turn it on. You should now see zero change on your pH monitor.
ok your saying once I calibrate it, if it moves after reinstalling the ground probe adjust my reading to what is was reading before putting in the ground probe?
with everything on and probe in it reads 6.80
with every thing off and with probe in or out it reads 7.94
I have 3 ballast with 2 36" T5HO lights on each ballast and everytime I turned on one ballast at a time and it drops .20 or so with each ballast ending up with 6.80. I wander if it's just the frequence my lights are putting out.
with everything on and probe in it reads 6.80
with every thing off and with probe in or out it reads 7.94
I have 3 ballast with 2 36" T5HO lights on each ballast and everytime I turned on one ballast at a time and it drops .20 or so with each ballast ending up with 6.80. I wander if it's just the frequence my lights are putting out.
gabbagabbawill
In Memoriam
That's weird that your ballast doesn't have a ground. Any explanation for this?
Let me break this down further, hopefully this will be easy to follow:
1. Unplug everything from power that is connected to the tank: Heaters, lights, pumps, etc.
2. Set up and calibrate the pH monitor.
3. Plug in ground plug.
4. Does the pH reading change?
a. If no, then move to step 5.
b.If yes, then re-calibrate the pH meter, then move to step 5.
5. Plug everything in that is normally connected to the tank. Turn all devices/ appliances ON.
When you turn everything on, the pH reading should NOT change, AND it will be calibrated properly. If it does change, post the results back here.
Let me break this down further, hopefully this will be easy to follow:
1. Unplug everything from power that is connected to the tank: Heaters, lights, pumps, etc.
2. Set up and calibrate the pH monitor.
3. Plug in ground plug.
4. Does the pH reading change?
a. If no, then move to step 5.
b.If yes, then re-calibrate the pH meter, then move to step 5.
5. Plug everything in that is normally connected to the tank. Turn all devices/ appliances ON.
When you turn everything on, the pH reading should NOT change, AND it will be calibrated properly. If it does change, post the results back here.
not sure why the ballast don't have a ground.
Ok, the my ph reading stayed at 79.87 till first set of lights came on then droped to 7.60. Then to 7.01 when second set come on then 6.80 when third set comes on. It goes straight back up as lights turn off.
The current in my tank did drop from 44v ac to 55mv ac after adding probe with all equipment running. So, I guess the ? is, is the voltage affecting any tank inhabitants or just my probe?
Ok, the my ph reading stayed at 79.87 till first set of lights came on then droped to 7.60. Then to 7.01 when second set come on then 6.80 when third set comes on. It goes straight back up as lights turn off.
The current in my tank did drop from 44v ac to 55mv ac after adding probe with all equipment running. So, I guess the ? is, is the voltage affecting any tank inhabitants or just my probe?
Mike31154
New member
The ballasts may be designed to be grounded through their case. I assume this is a retrofit T5 HO set up since it's a custom hood? The fact that there is no ground pin on the plug for the ballasts is somewhat disconcerting. What brand are they? Do you have individual reflectors for the lights and are they grounded? I found once I grounded the reflectors on my T5 retro set up, the induced voltage in the tank was reduced considerably. My ballasts (Workhorse 8) are grounded to the lighting fixture and each has a 3 pin grounded connector. If whoever built your set up used a cable with two pin ungrounded connectors, I would recommend having that rectified.
Finally, are you using a GFCI? That would also be recommended particularly if your ballasts are not grounded properly. Sorry this is not much help on your pH issue, but more of a personal safety concern.
Finally, are you using a GFCI? That would also be recommended particularly if your ballasts are not grounded properly. Sorry this is not much help on your pH issue, but more of a personal safety concern.
gabbagabbawill
In Memoriam
I agree with everything Mike said. ^^^^
I still can't tell if you followed my instructions regarding setting up and calibrating your pH meter.
I still can't tell if you followed my instructions regarding setting up and calibrating your pH meter.
They are a cheap brand GLO by Hagen I think. I was sold these before I knew anything about lighting. Yes I have a GFCI and I don't think I can add a ground to the ballast. They are incased in a plastic case. I do have individual reflectors and havent' tried grounding them. I don't think my ph is off it's just a fake reading. I will try a few experiments.
