Powerheads leaking voltage? Do you have a grounding probe?

This happened to me :(

I thought possibly leaking voltage... However wouldnt I get shocked? I also have everything running off a GFCI and figured it would be tripped with any stray voltage when I put my hand in the tank? No, I do not have a grounding probe.

It has nothing to do with voltage. Brand new powerheads are coated with the staff what is not toxic to the fish directly, but can reduce oxygen levels. And of course some fish is more sensible to low oxygen levels then others.

Same thing with sea hares. If harassed it may release a purple fluid into the water, which is not toxic, but may reduce oxygen levels and make some fish to suffocate.

If this is the case adding a air pump would probable help fish to recover.

Okay I added an air pump for extra aeration. I just assumed having 2000 gph pointed at surface achieved same result?

Update?

As of now most are getting better. I did another water change of 20 gallons today and jammed about 3+ cups of carbon in mesh bags into the sump. The flame hawk and clownfish pair are almost back to normal. Moved the trigger and 1 chromis back into display after I saw flame and clowns eating. However, dragonette, trigger, 2 chromis and anthias still hiding and breathing heavy, but not nearly as bad as yesterday. I am hoping they might eat tomorrow. I am relieved no more deaths, hope it stays that way. So good news for the most part except for butterfly fish came down with major attack of ich...

Butterfly with ich? Man, that sounds familiar :neutral: I've been battling that for a month now...

Glad to hear the others are alright. I feel so bad when I hear of these things happening.

Did you pull them and wash them? Or are you going to ride it out?

is it possible that something was in your tap water? sometimes the water company add chimical, especialy at this time of the year. It is not a good idea use tap water for aquarium use as I have seen it happen and read about it, some chimical killing all the fish in the aquarium. Depending on the dechlorinator, they should be very safe for saltwater. I know Seachem Prime is safe for satwater and I used it before without any problem.

9 fish in a 75 gallons is a bit overcrowded I think. It could have been a factor into your fish death by lack of oxygen maybe.

I have not taken the powerheads out and washed them yet. If they are not better by tomorrow, I will.

Ya I talked to water company today and they have been doing a "flush" in area the past while... however they said the chlorine has not been increased that much. I am using prime and has been fine in the past...

Do situations like this take awhile to fizzle out? It has been two full days since the episode, not sure if they should be back to normal by now? I have changed about 50 gallons of water on a total volume of 95 gallons or so. As far as bio-load, skimmer is rated for much larger tank with a heavy load and most of the fish are smaller than 3 inches. I am not sure how it could be lack of oxygen? I have tons of flow agitating the surface with an open top, is this not adequate? Thanks for all the help and suggestions!