. Do you vacuum the gravel regularly and/or do you use an under gravel filter? Or do you have
decor in which water may have become stagnant, such as artificial caves and rocks, which built up toxins that were then released during maintenance?
. Was work being done on your home in the vicinity of the tank (painting, sanding, spraying for insects or rodents, etc.)? Perhaps toxins were introduced during the work.
. Could a friendly visitor (child or pet) have introduced something into the tank or perhaps there's a drip from a ceiling pipe or vent that could have entered your system.
4. Sad to say nothing can live in water that has been through a home water softener. It is not even good for people to drink.
I would say that perhaps these fish were electrocuted.
6. I think the 5 organdies died of Chlorine. I don't think the softener was working correctly.
Ammonia spike, or possible electrocution from failing equipment.
8- MY FIRST THOUGHT WOULD BE THAT THE FILTER THAT WAS USED ON HER SOFTENER SYSTEM WAS DEAD AND NEEDED CHANGED. AFTER A WHILE THESE FILTERS IN SOFTENER SYSTEMS JUST STOP WORKING BECAUSE THEIR LIFE IS ONLY SO LONG AND CONSEQUENTLY WE MIGHT NOT NOTICE THAT THEY AREN'T DOING THEIR JOB BUT THE FISH DEFINITELY WOULD.
9. Based on the information given, my best guess would be that there was contamination of her water supply.
10.exhausted water softener did not remove chlorine it is best to use a dechlor or test for chlorine every time before using for water change. New Zealand
11. In response to the sudden oranda deaths, had she been painting, or using any chemicals around the tank which could have introduced toxic fumes into the water through the air lines?
12. could there have been a temperature crash? with the changes in the seasons a drastic temperature change could have opened the fish up to other causes of death?
13. My only assumption is that she did not monitor the temperature of the water and with a 33 percent water change, the fish may have reacted to a drastic change in temperature.
14. The Goldfish spawned causing an ammonia spike?
15. First of all my deepest sympathies to the owner. The water change is what stands out. It is possible that there was a contaminant in the tap water, such as pesticides that may have seeped into the water lines. If there were rainstorms that messed with water supply around the time the water change was done, water contamination is highly probable.
16. The only reason I can think of is that she lives in a northerly country and the tap water temperature is much colder at this time of year,and the sudden change in tank temperature was the cause. From Scotland
17.could it be an environmental problem, i. e., paint fumes, windex, toxic fumes? My heartfelt sympathies to the owner for her loss.
18. Last year I lost all of my fish due to a power surge that somehow entered into my aquarium and electrocuted my fish. (There was no mention if the fish in question were injured or otherwise internally deformed)
19. I don't like the sound of what seems to be a commercial water softner "culligan man"...Could it be that the tank reached the state of "no minerals at all"...also, some softeners use some sort of salt in their process...could softener chemicals have done them in??
20. Can be an electrolyte imbalance. Water softners removes electrolytes which is essential for fish health?
21. Since a water softner "re-generates" to make the hard water soft with the use of salt. If the softner didn't rinse properly you could have very salty water,especially first thing in the morning.
22. Obviously the Goldfish household is on city water (tap water). It's very possible there was a leak or a surge of corrupted water in the line. That happened to us and we lost 5 fish from 2 different tanks BEFORE the city came and told us they needed to shut off the water main and bleed out the lines (we had just done a water change and were baffled that we had lost fish soon afterwards).
23. If she did NOTHING DIFFERENT
then she had something DIFFERENT
she was getting from a trusted source that had worked for two years, as a starter. That could have been some chemical changes in the products she had been using, out dated/updated/changed in some way and/or the tap water source has been changed in some way. Additionally, she may have had the air and or filtration off longer than she thought.
24. Her water softener stopped removing chlorine (it needed a new filter for example) OR she switched softener pellets and they had some chemical in them which harmed the fish.
25. Too much SALT in tap water as a result of an imbalance in water softener unit or during the unit's recalibration cycle. Unless she used a hydrometer, she would not know.
Water softener unit malfunctioned and did NOT remove the chlorine and because no additional
dechlor was used, fish were poisoned.
26. The city's water department mandated an increase in chlorine or switched to chloramines. Activated carbon, water pillows, etc. usually don't remove chloramines. Also, carbon reaches a saturation point quicker than most people think. She doesn't use a water conditioner....and worse yet, the city usually doesn't send out a notice about such a change. I can smell increases in chlorine sometimes at my house when drawing water from the tap.
27. it doesn't say what the temperature was, here in New Jersey our water is coming out of the tap VERY VERY COLD! could temperature shock have done it to her orandas? (and I'm sorry for her loss also).
28. Was her water softener working properly? Did it break down without her knowledge? Are they on a well system? Did some kind of toxins or bacteria get into the water system?
29. I'm so sorry for this lady that lost her beautiful orandas. It's very sad. I send my condolences.
As for why this could have happened, I immediately suspect the water softener. I have never had a water softener but I know you have to add salt monthly so I would suspect something mechanical in the water softener either didn't effectively remove the chlorine or maybe something inside corroded and too much salt leeched into the water.