The loss occurred after a massive water change. I'm the one with the weird brown slime algae (it also turns white sometimes). My assistant was no longer under quarantine for COVID so she came over last night and did a water change on my 60 gallon tank. This tank primarily contains Rainbow fish as well as my Blue Phantom Pleco that I've had 2 years - made me sick. At over $100 I probably won't be replacing him for a while. I also had a couple of Dojos and some Leopord spotted loaches left in a 29 gallon tank. In fact, just that evening we decided to retire that 29 gal tank - there were only 5 fish in it - two dojos, the two Leopard loaches and a Bristlenose Pleco. All these fish except the Bristlenose Pleco was moved to the 60 gallon tank. The bristlenose went to a 29 gallon tank where there are more places for her to hide. I don't THINK the mere act of moving fish to a tank will kill 17 fish. There were already dojos in there so the other fish shouldn't have been too freaked by their crazy antics. The two Leopard loaches are pretty hyper so I suppose they could cause some stress but not THIS MUCH.
Our normal water change process is to remove the decorations, fake plants, sometimes live plants and rinse/scrub off all those thing. Every one was covered in the brownish slime, you have to clean each leaf on a plant individually - it just sticks to it. Then we start draining the water and cleaning the gravel of all the excess garbage at the bottom of the tank. We usually leave the fish in there - we remove 75% or so water depending on the size of the fish. After scrubbing down the walls and cleaning the heater and filter we start filling the tank with large buckets of water. To each bucket of water we add a bit of Prime to deactivate the chlorine and a small amount of Neutral Regulator by Seachem. The regulator is pretty cool in that it changes the PH of any water to 7.0. The PH of my tap water is 9.4 - way to alkaline to put any fish in it so I had to come up with some solution, But because of the various buffers in the water (GH=10, KH=5) over a period of 5-7 days the PH will drift downward to about 6.4 which is still acceptable for most of my fish - by then we are ready to do another water change (always once a week) and it re-sets the PH to 7. I'd like to understand why it drifts down but that's a question for another day.
We're both pretty good at following this pattern every week, no matter who is changing the water but of course sometimes you get complacent and forget to pay attention to what you are doing. That's the ONLY explanation I have for why 17 fish were dead when I got up in the morning, If anybody has any other ideas I'd appreciate it - we are just heartbroken. I'm so glad my bristlenose was in a different tank because she is a big favorite of mine. All the Dojo's survived. Two of the silver female rainbow fish survived and one of the female Albino millennium rainbow fish survived. Nothing else - lost pretty much my entire collection of Rainbow fish which I just purchased in mid-October.
I removed the surviving fish to my 29 gal tank which is becoming pretty crowded so they can't stay long. The 6 Dojo's alone are 8" long. As an attempt to get rid of the brown/white mold We are thinking about removing and cleaning the gravel in the two tanks we plan on using from now on - in fact we might even replace it but that gets pretty expensive. My assistant found something on the internet that supposedly kill this type of mold - they call it white mold and it's actually a fungus. She wants to clean all the decorations and the gravel with this stuff - (NOT the fish). I'll wait until it gets here and read the fine print before I let her use it, especially on the gravel - but we've had problems with losing fish occassionally ever since that brown/white fungus showed up so we want to do everything we can to eradicate it. I don't think the fungus was responsible for killing the 17 fish but what was responsible? And why did some rainbowfish survive when the majority died?
Any other good fungisides out there that are aquarium/fish safe? Do you think we just forgot to add something like Prime when we changed the water? I know we added the Neutral Regulator because PH was at 7l Ammonia was a 1,0 (no surprise since 17 fish died and floated around for a few hours at least, Nitrites were zero and Nitrates were 5.0 - pretty much what they always are.
Any help is appreciated.
Our normal water change process is to remove the decorations, fake plants, sometimes live plants and rinse/scrub off all those thing. Every one was covered in the brownish slime, you have to clean each leaf on a plant individually - it just sticks to it. Then we start draining the water and cleaning the gravel of all the excess garbage at the bottom of the tank. We usually leave the fish in there - we remove 75% or so water depending on the size of the fish. After scrubbing down the walls and cleaning the heater and filter we start filling the tank with large buckets of water. To each bucket of water we add a bit of Prime to deactivate the chlorine and a small amount of Neutral Regulator by Seachem. The regulator is pretty cool in that it changes the PH of any water to 7.0. The PH of my tap water is 9.4 - way to alkaline to put any fish in it so I had to come up with some solution, But because of the various buffers in the water (GH=10, KH=5) over a period of 5-7 days the PH will drift downward to about 6.4 which is still acceptable for most of my fish - by then we are ready to do another water change (always once a week) and it re-sets the PH to 7. I'd like to understand why it drifts down but that's a question for another day.
We're both pretty good at following this pattern every week, no matter who is changing the water but of course sometimes you get complacent and forget to pay attention to what you are doing. That's the ONLY explanation I have for why 17 fish were dead when I got up in the morning, If anybody has any other ideas I'd appreciate it - we are just heartbroken. I'm so glad my bristlenose was in a different tank because she is a big favorite of mine. All the Dojo's survived. Two of the silver female rainbow fish survived and one of the female Albino millennium rainbow fish survived. Nothing else - lost pretty much my entire collection of Rainbow fish which I just purchased in mid-October.
I removed the surviving fish to my 29 gal tank which is becoming pretty crowded so they can't stay long. The 6 Dojo's alone are 8" long. As an attempt to get rid of the brown/white mold We are thinking about removing and cleaning the gravel in the two tanks we plan on using from now on - in fact we might even replace it but that gets pretty expensive. My assistant found something on the internet that supposedly kill this type of mold - they call it white mold and it's actually a fungus. She wants to clean all the decorations and the gravel with this stuff - (NOT the fish). I'll wait until it gets here and read the fine print before I let her use it, especially on the gravel - but we've had problems with losing fish occassionally ever since that brown/white fungus showed up so we want to do everything we can to eradicate it. I don't think the fungus was responsible for killing the 17 fish but what was responsible? And why did some rainbowfish survive when the majority died?
Any other good fungisides out there that are aquarium/fish safe? Do you think we just forgot to add something like Prime when we changed the water? I know we added the Neutral Regulator because PH was at 7l Ammonia was a 1,0 (no surprise since 17 fish died and floated around for a few hours at least, Nitrites were zero and Nitrates were 5.0 - pretty much what they always are.
Any help is appreciated.
thats horrible to go through. 
