Why fish die when water parameters are WNL -- a discussion

[Mmathis]

I thought I would start this thread, sort of following on the information being discussed in @bettasngoldfish's thread.

So, when you have mysterious deaths (and especially a massive die-off like Maria suffered).....your water parameters are WNL and you can't find evidence of a pathogen or predator attack....... Where do you look from there?

The obvious that we hear and address all the time:

• pH crash
• ammonia/nitrite levels
• low dissolved oxygen
• over-stocking
• bacterial or paracitic outbreak
• which most of the above can be lumped under "water quality issues"
• predators

Then any others [feel free to add to the list]:

• Sometimes fish just die....maybe due to previous stresses or from genetic predispostion
• Toxins in the water.....due to lawn run-off
• Toxins in the water.....due to aerasolized products [ie -- mosquito control]
• Maybe toxins due to something we inadvertently add to the pond........a plant or ornament....
• __________________
• __________________
• __________________

What about predatory pond insects? They mostly [I would assume] go after the smaller fish such as fry, but COULD they ever be an issue if you have fish dying for no aparent reason? Of course, not the cause of a massive die-off, but what about the occas. death here & there? I know I have those giant water bugs in the pond -- have seen them -- and they are known to attack and kill larger critters..... Just a thought......trying to cover all bases......

 

[bettasngoldfish]

Good idea Maggie

adding new fish without quarantine

 

[Mmathis]

Also add summer heat! Sun + shallow water = heat = low oxygen levels.

 

[MitchM]

-consider where you bought your fish from - was the supplier reputable or are they medicated feeder fish that had a short life expectancy to begin with
-vandalism - rare, but still should be considered
-addition of quick fix chemicals without understanding their effects and limitations
-other extreme weather events - hail or lightning

 

[Dave 54]

Lack of fish keeping knowledge. lack of fish health Knowledge.
Lightening strike direct or indirect , overdoses due to insufficiant knowledge of size and gallonage of pond .
Under dosing pond due to insufficiant knowledge of size and gallonage of pond
Water turning toxic because of a rare coming together of high Ph-salted pond water and formalin.
Overfeeding

Dave

 

[Mmathis]

Giant water bug and gold fish -- poor thing never stood a chance..... I wonder what size the fish is.

Could a fish be attacked by one of these monsters, but get away only to die from its injuries? I watched another video.....well, only part of it because it was a set-up for the bug to get the fish and I didn't like that....where the water bug was hunting/stalking some goldfish. I suspect that I do have these in the pond.....oh my!

 

[Meyer Jordan]

So, when you have mysterious deaths (and especially a massive die-off like Maria suffered).....your water parameters are WNL and you can't find evidence of a pathogen or predator attack....... Where do you look from there?

A giant water bug would leave some evidence of attack on a fish- lacerations puncture marks, missing flesh, etc. Such evidence is easy to see. Maria did not mention observing any physical trauma to any expired fish.

 

[MitchM]

I have those waterbugs in my pond and I am thankful for that.
Last summer I started with 20 ruby red minnows and by fall I had over 1000.
Ths spring I would sometimes pull 20 of these waterbugs out of my skimmer each week. The minnow population would drop and soon after I would not have any more water bugs. Now I have over 1000 minnows again so I expect to see the waterbug population increase again.

It's all part of natures balancing act.

.

 

[Dave 54]

A giant water bug would leave some evidence of attack on a fish- lacerations puncture marks, missing flesh, etc. Such evidence is easy to see. Maria did not mention observing any physical trauma to any expired fish.

Not only that You'd need one hell of alot of waterbugs to attack her fish in a coordinated attack over one night

Dave

 

[Beckie]

Poisonous toads (Florida) laying eggs, fish eat eggs and die. I'm wondering if that's my problem since I ruled out everything else I can think of. Never heard of it before but found articles that bring up the possibility. Weird things happen in ponds, right?