Added powerhead to tank - instant death!?

[welchrock]

Ugh I'm not happy about this one, and am appealing to anyone who might have some insight:

I bought a Hydor Koralia 1 (400 gph) for my 46G tank, to both improve circulation and improve the efficiency of my existing canister filter.

Within 20 minutes of installing it, I noticed lots of excitement from my tetras, but totally listless behavior from my honey gourami's. The remainder of my fish seemed to be unaffected. One of the honey's in particular seemed to be in AWFUL shape, totally out of the blue. Prior to installing this powerhead, I had not had a death or even a sick-looking fish in months. One of my honey gourami's was dead within a few hours.

Here's what I'm thinking - when I installed the powerhead, I stressed the fish out a bit, probably more than when I do my weekly water changes. However this still doesn't explain the sudden downfall of the honey gourami's. My only thought is that the powerhead stirred up significant amounts of *stuff* and ammonia from the bottom of my tank, and drastically changed my water's chemistry within mere minutes.

Since I have turned off the powerhead (it was only on for 20-30 minute), things seem to have gotten somewhat back to normal. I have hopes that the surviving honey gourami's will recover and that the rest of my fish will continue to remain unaffected.

Any help on this topic is MUCH appreciated, because besides my one theory (in bold above), I am totally lost on what happened and how I could negatively affect the health of my tank so quickly.

Not even sure if I ever should use the powerhead again....at the very least I won't until I do a significant (40%) water change.

I don't want to lose any more fish - HELP!

[GoodMike]

IMO if the power head "stirred up significant amounts of stuff" then other fish would be affected as well, so i would rule that out. i would say that it is unusual for something like this to happen, so i dont know what to say. The use of a power head, especially one that in reality isnt pushing a ton of water around, should not cause fish to die...
All fish that i have had adjust rather quickly to an increase in flow, all the way from anbantids to zebras . i would personally try looking for another cause

[welchrock]

oh i'm definitely looking for another cause but with nearly no health problems the last few months, it's hard not to look at the easiest explanation for causation. on the plus side, the issue seems to be only affecting my honey gouramis, and i still have hope that the 30 or so minutes the powerhead was on didn't do that much damage.

for those with experience with powerheads in tropical tanks - what should do about turning it back on? i loved the brief period of extra movement in the water - the tetras looked great, my moss/plants were all swaying beautifully...and i really think my tank as a whole could use more circulation.

[Blue Cray]

Have you tried putting air stones at one end? It helps on smaller tanks alot to get the flow going.

[welchrock]

i'm not even sure how i would do that - the output opening is larger than a quarter...and really doesn't have anywhere where i could wedge an airstone.

i may try blocking some of the input with some filter floss, to slow the flow and let the fish acclimate better.

[emc7]

Did you smell sulfur? The only thing I've heard about stirring things up is that if you disturb an "anaerobic pocket" you can release toxic hydogen sulfide gas.

[welchrock]

Ahhhhhhhhhhhhhhhhh finally something that at least in my mind, might explain the extremely sudden and serious health issues. what on earth is a anaerobic pocket and how does it form? would it have somehow been hidden in one of the corners of my tank and my fish were just avoiding it?

i'm away from the tank now but will take a sniff within a few hours.

[GoodMike]

if it was caused by anaerobic pockets built up in the substrate, all your fish would have been negatively effected. Your tank also seems to be pretty well planted, which usually helps get rid of the chance of these pockets forming. IMO this would not be the source of the problem if only one type of fish was effected.

[welchrock]

Ok while my honey gourami's have not gotten any better or worse, I've come up with a better way to verbalize what is happening to them - they look like they're paralyzed. Perfect coloration and fins, they just barely move. When they do move, it's mostly because of a small current or desire to be in a slightly different position...they flale to move, and then go back to being motionless and totally still...although in a normal position. All motion is generation from their tails - not their 'arm' fins like is normal.


if there is a piece of the puzzle i've left out - it may be this: on thursday I got four new fish - panda corys. from all indications they are perfectly healthy, had been at my LFS for about a month and are from a LFS i would trust my life with. the corys behavior has been unchanged since my 30 minutes of powerhead-use, and to repeat an important fact - my honey gourami's were acting FANTASTIC before the addition of my powerhead (lots of swimming, socialization, pecking at java moss etc...same as always).

[GoodMike]

Originally Posted by lohachata

hmmmmm..there is a missing equation here.something not mentioned.

agreed

"if there is a piece of the puzzle i've left out - it may be this: on thursday I got four new fish - panda corys. from all indications they are perfectly healthy, had been at my LFS for about a month and are from a LFS i would trust my life with. the corys behavior has been unchanged since my 30 minutes of powerhead-use, and to repeat an important fact - my honey gourami's were acting FANTASTIC before the addition of my powerhead (lots of swimming, socialization, pecking at java moss etc...same as always)."

DING DING DING. we have an answer. OK, so while a fish may look fine, that doesn't mean they are. The introduction of new fish always introduces new potential problems. The power head stressed the fish out some (obviously) and a fish under stress is WAY more likely to pick something up that it normally would be able to fight off just fine. THAT makes way more sense than the power head killing them.

IMO the introduction of the new fish + stress = sick fish

[welchrock]

all of that equation = sad face for me!

what would be the best way for me to proceed?

(i took the powerhead out entirely, in the off-chance some/all of this was caused by a chemical residue left from manufactoring)

[emc7]

I think you would have noticed the rotten egg scent. Could be something else. Did you do a large water change at the same time?

[welchrock]

i did not do a water change when i installed the powerhead. i did one a day or two prior to getting the new fish.

emc7 - smelled it less than an hour after your post here about sulfur, and the tank smelled quite healthy - like a nice pond.

lohachata - glad someones on this side of the fence - because that is still my primary thinking.

[jones57742]

wr:

I have not entered this dialog previously but as you have now published all known parameters which may have affected the sudden death syndrome which you experienced but I will "chime in" only with takes on previously presented items (ie. I cannot think of anything else):

• [1] Although discarded early in the thread the turbulence in the tank may have indeed really "stressed out" the fish. Although you did not publish the model of your cannister filter if it is circulating 10X/Hour then the power head which you induced will yield currents in the tank sufficient to produce a turnover of 20X/Hour.
  • [a] It is my understanding that this magnitude of current is employed in the SW world, is near the upper limit for even a hillstream loach river tank and is, IMHO, "a bunch" for a typical community tank.
  • [b] I am not familiar with gouramis but I am familiar with the genus of the other fish in your tank and, IMHO, they, especially the Cory's and BN Pleco, are not happy campers with the turbulence/velocities in your tank.

• [2] Not discarded was the concept of the release of anaerobic gases due to the turbulence produced by the induction of the power head.
  • [a] IMHO this is a probable cause and could be due to not only the release of gases which are produced by anaerobic digestion but by the introduction of pathogenic bacteria which are lethal or toxic to fish.
  • [b] I am familiar with "something like this" as all my fish were healthy one night and the next morning I awoke to find several dead or dying Yoyo's, all the Gold Nuggets and Queen Pleco's were dying and the Sterbai Cory's were exhibiting symptoms of severe stress. WC's did not help and the mid-depth fish began exhibiting symptoms of severe stress. "Just on a chance" I placed a ton of activated carbon in my filtration process and TG I had joy. The tally was unfortunately all of my GN's, all but one of my QA's, all but two of my Yoyo's and one of my Sterbai.

• [3] You briefly mentioned the release of toxic/lethal substances from the power head. IMHO this scenario is probable also. The QA/QC of these devices are obviously not to NASA's standards.

TR

[welchrock]

wow thanks for all that insight jones57742, much appreciated.

i don't have that much to add at this time, but i would like you to know my filtration: Magnum 350 canister. a few days prior to this incident, i put 70% new activated carbon in it so i'm hoping that speeds up my tank's recovery.

as for my fish, they seem to be about the same. all non-honey gouramis appear unaffected, but one honey gourami is near-death while another looks better and i put his chance of recovery at 50/50.

still confused on when/if/how i can utilize this powerhead in my tank to improve circulation, temperature consistency, oxygen levels, filter efficiency etc. i purchased it because the circulation and water movement in my tank was visibly insufficient.

[welchrock]

maybe its time to put the powerhead in storage and put it into a much larger tank down the road.

[Obsidian]

If you want to increase the circulation you can add an airstone bubble wand. It would not have to be big, but in my experience the wands create some circulation as well as the bubbles themselves. I would put the wand at the opposite end of the tank from the filter. I have done this in my 10 gallon with a very small wand and it works great. In a 46 gallon I would put it along the back wall rather than along the side wall. This will create more movement over a larger portion of your tank. The current it will create is also something that the Gourami 's can just avoid. In my 20 gallon my Gourami does not avoid the airstone, but it is a single stone not a wand. he never goes right into the bubbles but he does go around it.

Just an idea There are probably several solutions.

[welchrock]

Update: the honey gouramis seem to be literally rotting. their fins are becoming white and frayed, and are falling apart...especially their pectoral fins. for my two cents, this is a sign of something other than stress.

luckily the rest of my tank is 100% perfect...at least for now.

[emc7]

Sounds like disease, maybe fin-rot. He didn't say stress was the only cause. He said stress + new fish which carry new disease = stressed, diseased fish.

[Obsidian]

As said before: When a stressor is added to a tank (such as the powerhead) it can bring out underlying health issues. I believe that if nothing else the powerhead played this type of role in the situation.

Gourami's do need more still waters so as long as you plan on keeping them I would not go with a powerhead of that nature. There may be a small gentle one you could use. Or you could go with the bubble wand.

If you have a QT tank I would put the Gourami's in there with a light salt solution to help their fins.