Stray voltage - help!

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nzafi

Goliath Tigerfish
MFK Member
Mar 14, 2008
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I have been having problems with my 180g. My Aimara was getting fin rot which didn't make sense based on the diet, water parameters and water change schedule. He also not has hith. I think I found the problem is stray voltage. I test for it today and when the heaters are off its around 4 volts but when the heaters come on it shoots up to 55-70.

Isn't this a problem? I believe under 50v is fine but technically it should always be consistent and if it increases with heaters coming on it means there is current going into the tank.

Thoughts? Feedback?
 
May just be the socket the heaters are plugged into? Test with a different one and if not I'd replace them just to be sure. (Or find out which one it is and get rid of that one)
 
If I suspected that, I would test the water, not the heater, the power strip, the outlet, the fuse box or the power line coming into the house. Ime, its better to confirm a problem exists, rather then to start fixing possible sources of a problem that might not exist.


Here's an example of a testing process for stray voltage.
https://www.thespruce.com/curing-stray-voltage-in-saltwater-aquarium-2924174


The overwhelming number of fish that get fin rot or HITH do not have faulty electrical currents in the tank. And iirc, people think both are caused by bacteria or fungus, and ultimately from poor conditions.

Have you posted your water parameters?
 
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If I suspected that, I would test the water, not the heater, the power strip, the outlet or the fuse box.

https://www.thespruce.com/curing-stray-voltage-in-saltwater-aquarium-2924174


The overwhelming number of fish that get fin rot or HITH do not have faulty electrical currents in the tank. And iirc, people think both are caused by bacteria or fungus, and ultimately from poor conditions.

Have you posted your water parameters?

That's actually how I tested. Prove in water and then when the heaters come on, it jumps by 50+ volts. Need to narrow it down to which heater and replace it. Unbelievable because they're all less than a year old.
 
Okay thanks. I wasn't clear that you had tested the water since testers work on wall sockets, power strips, devices, etc. You could swap out heaters and immediately determine if it's a heater or something else. If two heaters cause the same problem, I would doubt it's a heater.

I would agree with Chub_by that it's some thing else. If it's not a heater, then try swapping power strips or wall outlets and that should narrow it down to the source.

Everything electrical can develop a fault, although the least likely one is the line coming into the house, it can happen in the socket or any device attached to the socket.

Good luck on it not being a socket, since that makes it unusable until someone fixes it.
 
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Okay thanks. I wasn't clear that you had tested the water since testers work on wall sockets, power strips, devices, etc. You could swap out heaters and immediately determine if it's a heater or something else. If two heaters cause the same problem, I would doubt it's a heater.

I would agree with Chub_by that it's some thing else. If it's not a heater, then try swapping power strips or wall outlets and that should narrow it down to the source.

Thank you. Good suggestion. Didn't think about it being a wall sockets or power strip issue. All 3 heaters are in the same socket and power strip so if pulling out the heaters doesn't work I'll know it's the socket or power strip.
 
Ok, I'm slightly lost here. How would the stray voltage find its way into the tank from a bad socket or power strip, if it has no direct contact with the water in the tank? It seems to me that the voltage jumping when the heaters come on points to the electrical components of the heater coming in contact with the water through a leak in the heater. The stray 4V during the other times could be residual from these times, or they could be from the friction of the water going through the filtration system.

I'm not saying any of you are wrong, I am just really interested to know how that could happen.
 
Unlug everything one at a time. If a piece of equipment that's unpluuged drops the stray, replace it. And it could be more than 1, anything from heaters to lights, to pumps.
There are also grounding probes available that help.
 
So this is a bit ridiculous. I found that a lot of my equipment was sending tons of volts into the aquarium. Quick summary:
Nothing connected but air pump: 8v
Each 300w finex heater: jumps from 8 to 34v
Finnex controller: jumps from 8 to 100v
Power head: jumps from 8 to 30v

I'm not an electrician but for some reason when everything is connected it maxes out at 100v.

For now I have disconnected everything but 2 heaters that's keeping me at like 40v. What is hard to gauge is that it's not volts that matter but current but I don't think there is an easy way to measure that.

Looks like I'm buying a grounding prop for the tank and I need to figure out my heater/controller scenario.
 
I have found that heaters are one of the more common culprits, and need to be regularly replaced. If not they can get worse over time, and without warning "you" can end up with a large enough shock to stop your heart, when in combination with the other culprits when you put your hand in the tank.
You can usually notice the fist signs of stray voltage if you have a tiny cut on your hand and do a water change. That's when I start unplugging stuff, and replace it when found.
 
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