Electric Current killed my Betta HM fry....?

Hi Guys

So I was away for our conference for over a week, and just before I left, i realised there was a small electric current in my 3 foot tank with about 50 + HM betta fry in it, I only realised this as I had a small cut on my finger.

It was my internal power head causing the current....this means that the fry was exposed to this current for about 3 weeks.

When I got back all except 4 had died, funny thing is I have 1 x neon tetra in there, he is fine, I also have all my breeding males in there, they are all fine!

So, my question is, can this electric current effect my fish so badly and kill them, even after I have removed the power head, was the damage allready done?

 

IMO and from what I have heard nope as they are not earthed. when you stuck your finger in the tank you were creating a path to earth so the current flowed through your body down to earth.

 

True...but surely they will still feel this current as it was running through the water, and water is a conducter? Earthed or not?

 

Is this not a water quality issue due to removing the powerhead and some sort of buildup?

 

I have a double sponge filter, and a HOB filter in as well, I do daily water changes, mornings and afternoons, feeding was done once a day by my neighbour. During the week no water changes was done just top ups due to evapuration.

The reason why I keep the Neon in the tank is to pick up water quality issues, as they are sensative to water quality, well allot more sensative then my Bettas.

And she is perfectly fine and healthy.

I use exactly the same filtration in my other tanks, and same was done to my other fry in terms of water top ups and feeding, and those fry in the tanks are doing great with no losses @ all during the week I was gone?

 

Ok, so not a water issue. I know we did have a discussion somewhere on the site about someone being killed due to current in his tank. I would have thought along the same lines as @karele. Like the guys that work on live powerlines. They are fine as long as they don't earth...