First set back

Did some voltage measurements. Total AC voltage in my tank is 40V!!!! Only 2V with everything off.

I went and measured all the equipment. Every single pieces adds anywhere from 2V to 12V. I mean every single one. They can't all be bad can they?

Surprised at worst offenders. But i guess it makes sense:
Two Ecotech pumps! They add 22V alone. I am certain that is via induction since they are magnetically coupled and there's no electrical elements submerged.

I guess I'll go get a grounding probe.

Is 40V normal for a 55g tank? Jeez. Amazed it does not shock me.

 

Did some research

checking around , and its not uncommon for older items to leak 5 - 10 volts each
thus if you have 2 power heads, a heater and a Hob filter for example- you can easily get to 40 it seems

so your example is not uncommon around the www based on the last 20 mins searching done

Steve

 

Thanks Steve. I think i'll invest into a grouding probe just the same. Why not?

Tested water at LFS. All params exactly as I said they were. They have a diff mag kit, and it read 1600.

LFS guy said mag must be from the reef crystals salt mix. He said it's on the high side but nothing to be alarmed about. He said i could add some fresh RODI water over the course of the few days to bring salinity and mag down a lil.

He agrees it had to be Oxygen. He said 40V is normal. He said in some tanks they run it's reading higher.

 

What mag test are you using? Some can be confusing to read such as the salifert... Make sure you are testing correctly because if you didn't add magnesium, and you are using rodi, 1700 is sort of impossible isn't it?

Yup you are right. Most people measure in dKh, along many tests.

 

If Ammonia, Nitrite and Nitrates were fine, my guess is oxygen. Regardless of everything else, from excellent to dead occurs as a result of something drastic. Even with high numbers during a nitrogen cycle, death can be avoided. I have a Rock Beauty, and regardless of the level of difficulty found on most websites, he's a very hardy fish once acclimated to the aquarium. Either you're not giving us the whole scoop on the condition of the fish prior to, or we're missing some details.

To add: I would still be quite surprised if your fish died over night from voltage in the tank. Especially since nothing new was added. Most often signs of stray voltage are indicated through such things as fin rot, head and lateral line disease and unusual behavior. On occasion it may result in death, but from my experience, it is usually rare that a fish didn't show any obvious signs prior to its death.

 

This happened to a couple inhabitants in my tank when I first set it up. Died for no reason, levels were fine and had plenty of oxygen. Sometimes in new tanks other factors and chemical imbalances can cause death in weaker fish. The tank environment isn't entirely stable after a few months, so these things happen.

Maybe the toxins from the coral were leached also, do you run carbon?

 

Nvinz: All fish were fine the day before. No unusual/stressed behaviour. The two remaining look a lil shy/stressed this morning. That is the whole scoop.

K3rack: Yeah, i got a sock of carbon in the powerhead filter and another sock of SeaGel (carbon + phosguard) in the skimmer return chamber. What toxins are we talking about here? Polytoxin from zoas?

 

True, also, the Ecotech Vortech pumps do not have any electrical components in the water. So, this has to be electromagnetic induction. http://en.wikipedia.org/wiki/Electromagnetic_induction Basically, the moving water is the conductor and the MP10 is producing the magnetic field. Not a problem at all, or most of us would be unable to keep fish.

AS to O2, the skimmer adds a lot of O2, so that seems unlikely. Maybe if you were overstocked, but your not.
The Need to Breathe, Part 3: Real Tanks and Real Importance by Eric Borneman - Reefkeeping.com

Could be aggression, predator, infection. Sometimes diseases hit some fish, but not others. Could be stress from something compromised their immune system for example. Or they both ate something toxic, never know. I can't come up with anything based on the info in this thread, there are too many unknowns sometimes.

 

Thanks m2434.

When adding calcium or rising alk (2-part bottles), it says to pre-mix with a cup of water which I always do. Then I add that cup into the tank. Even doing that, you can still see the smoky plume from the chems.

If not an oxygen issue, I wonder if perhaps those fish somehow inhaled a bunch of that. I bet that would not be good for them.

 

No Problem, sorry I can't help with the cause...

As to the "smoke" this is just magnisium hydroxide. It forms when the magnesium in solution is exposed to high pH and combines with hydroxise ions. Such as when you add a buffer. However, it is transient and the magnesium becomes soluble again once the water disperses. So, also no big deal, happens to everyone.