Protein Skimmer Power Bar Failure Death Toll....

[Aquattro]

The thing with oxygen is not adding it, but removing CO2. any water surface movement should off gas the CO2 in the system, making the water absorb more O2. If the power heads were causing any type of water surface movement, you should have been fine. Lots of tanks run without a skimmer at all, and do just fine. Not sure what to look for, but I can't see this being from the skimmer turning off.

[kien]

Originally Posted by Aquattro

The thing with oxygen is not adding it, but removing CO2. any water surface movement should off gas the CO2 in the system, making the water absorb more O2. If the power heads were causing any type of water surface movement, you should have been fine. Lots of tanks run without a skimmer at all, and do just fine. Not sure what to look for, but I can't see this being from the skimmer turning off.

I have a skimmerless tank too and ya it has done just fine. Thankfully it is not my primary source of oxygen or surface agitation on that tank tho and there aren't a lot of fish in there. But, what if a tank had it's powerheads pointing down and there was little to no surface agitation? It looked to me like the skimmer was the only thing agitating the surface and as you said, CO2 needs to exhaust from the tank as well. Loss off primary oxygen source and surface agitation to expel excess CO2 to me spells doom. I don't see why the loss of a skimmer CAN'T be the cause. Sure, there MAY have been some other cause but given the facts we know, the skimmer seems to me to be the most likely culprit by making the least number of add assumptions. Fish are perfectly fine one day, then skimmer dies over night, fish dead the next day.. No, can't be the skimmer??

I realize that a lot of people, myself included run skimmerless just fine but I don't see that being the point here. My skimmerless tank and your skimmerless tank is not the same as this skimmerless tank. We all know perfectly well that every single tank is different. Two people could be running the exact same setup but still get different results. Just because you are successful without a skimmer doesn't mean another tank without a skimmer will be equally successful. The same applies to pretty much everything in this hobby, biopellets, zeovit, salt brands, RO water vs tap water, etc..

[Aquattro]

Kien, I can't really disagree with you, as it does seem that obviously that was the deciding factor. I can't tell why, but the skimmer appears to have been the "last straw", indicating some other factor in play. My point, I guess, was that it "shouldn't" have been the skimmer, as lots of skimmerless tanks don't have powerheads pointing at the surface, or other forms of noticeable surface agitation. Maybe a too heavily stocked tank, high CO2 content in the room, etc. Lots of factors could have contributed, with the skimmer being the buffer. No skimmer, tank crossed the boundary into this situation.
It's always tough to diagnose something like this online. I'll revise my comment to be " while it's obvious the skimmer was the major contributor, it shouldn't have been", meaning I think there was a secondary cause.

[kien]

Being in Yellowknife your house must be fairly sealed up for a good portion of the year. Curious, what form of ventilation do you have? This is yet another variable that is different from some other people. Not too many reefers in Yellowknife I dont think. There is typically a major in house CO2 spike during the winter months especially for cold weather climates. The skimmer could have been keeping O2 and CO2 in the tank in a fragile balance, but once it was gone, the scale tipped in the wrong direction.

Sure, a lot of people can get away with not using a skimmer or not having to point their powerheads at the surface, but those same people may not have the same environmental challenges that your tank might be faced with being in Yellowknife. Again, there are so many variables from one tank to the other that you can't always say, "hey, well, Fred over there has the exact same tank as me and he doesn't use a skimmer, so I'll be perfectly fine without one too". "And hey, Joe over there doesn't point his power heads at the water surface, so why should I??" We all know the hobby doesn't work that way. It may very well be that your tank needs more aggressive oxygenation and gas exhaust than other tanks.

[ensquire]

Originally Posted by kien

Being in Yellowknife your house must be fairly sealed up for a good portion of the year. Curious, what form of ventilation do you have? This is yet another variable that is different from some other people. Not too many reefers in Yellowknife I dont think. There is typically a major in house CO2 spike during the winter months especially for cold weather climates. The skimmer could have been keeping O2 and CO2 in the tank in a fragile balance, but once it was gone, the scale tipped in the wrong direction.

Sure, a lot of people can get away with not using a skimmer or not having to point their powerheads at the surface, but those same people may not have the same environmental challenges that your tank might be faced with being in Yellowknife. Again, there are so many variables from one tank to the other that you can't always say, "hey, well, Fred over there has the exact same tank as me and he doesn't use a skimmer, so I'll be perfectly fine without one too". "And hey, Joe over there doesn't point his power heads at the water surface, so why should I??" We all know the hobby doesn't work that way. It may very well be that your tank needs more aggressive oxygenation and gas exhaust than other tanks.

Houses here are sealed up tightly yes. And in this older home we have a very passive exchange system. Just a couple of vents in washrooms and kitchen.
I have to get my test kit back from work and retest everything again to verify things. But everything left in the tank is healthy, happy, & hungry again today.
I agree with the idea that the skimmer shutting down for 12 hrs shouldnt have killed 7 previously healthy inhabitants, and until I confirm parameters I (we ) just don't get it .
I will change angle of powerheads if everyone thinks that that could be a problem, but the fluval return does point at the surface and agitates quite well. Maybe the fluval needs to be taken out of the equation , maybe it is a nutrient trap?

Final Tally
2 Pink Clowns
Bi color Blennie
Flame Angel
2 cleaner Shrimp
Coral Banded Shrimp

[daniella3d]

+1, That's what I meant as well. Not that it did not cause the death of fish, but rather it shouldn't have caused the death of all these fishes.

There is some real problems with that tank that must be addressed before this happen again, skimmer or no skimmer.

Originally Posted by Aquattro

My point, I guess, was that it "shouldn't" have been the skimmer, as lots of skimmerless tanks don't have powerheads pointing at the surface, or other forms of noticeable surface agitation.

[kien]

Hindsight is 20/20. It is easy enough to say now that the skimmer going titz up should not have killed your fish, but how could one have predicted that before hand? Like so many people here suggested, their tanks are fine
without a skimmer or powerheads pointing at the surface so yours should be fine too. Well, what happend when the skimmer went offline? How could you possibly account for all possible scenarios that are affecting your thank, many of which are intangible.

No doubt this hobby is tricky like that. It is difficult for anyone to predict these sorts of things. Running BioPellets shouldn't nuke my tank, but can it? Will it? Running ZeoVit shouldn't nuke my tank, but can it? Will it? This heater shouldn't die, but can it? Will it? Turning my skimmer off shouldn't nuke my tank, but can it? Will it?

[Aquattro]

Originally Posted by kien

but how could one have predicted that before hand?

Not sure of the point here. I don't think anyone is trying to assign blame for not predicting this could happen. It's just more of a surprise that this can happen, and at this point, hindsight is all we have. Point is, stuff died. Maybe some of the suggestions can alleviate it happening again? Or to someone else...

[ensquire]

Originally Posted by Aquattro

Not sure of the point here. I don't think anyone is trying to assign blame for not predicting this could happen. It's just more of a surprise that this can happen, and at this point, hindsight is all we have. Point is, stuff died. Maybe some of the suggestions can alleviate it happening again? Or to someone else...

Thats the biggest advantage to cruising these forums, the wealth of info is unparalleled and a real resource as I am now learning.
If it prevents me from having recurring problems and keeps it from happening to others we have acheived our goals..

Fluval is going BYE BYE
Water change to follow

I will post further results

[kien]

Originally Posted by Aquattro

Not sure of the point here. I don't think anyone is trying to assign blame for not predicting this could happen. It's just more of a surprise that this can happen, and at this point, hindsight is all we have. Point is, stuff died. Maybe some of the suggestions can alleviate it happening again? Or to someone else...

Agreed, I don't think anyone is passing blame here, nor should they! However, there does appear to be a lot of predicting going on as to how this tank should or should not have behaved in this scenario but it is hard to predict these sorts of things.