So I get home from work this evening to find my water very cloudy and 90% fish wiped out. To say I'm gutted is an understatement!
I have a 125l Fluval Roma with U3 filter and two Chinese filters. CO2, EI dosing with salts and trace elements. My weekly 50% water change was due yesterday, which I did using Prime at .3mm per 12l bucket. Before the change my nitrates were somewhere between 50 and 100. After the change they were 25. Before the water change my tank was cycled, 0 on ammonia and nitrite. I use Salifert to test these particular parameters. As well as the water change I clean my filters on Mondays, using old tank water and this week I did a massive clean up. I took all my rocks out and scrubbed them with the tooth brush I use for this. Took all my plants out and gave them a clean, removing dead and dying leaves. I've been having problems with plant growth and this was part of the remedy required to improve on this. Nothing came into contact with anything it shouldn't have. This I am certain of.
I did increase my CO2 last week, but for some days there has been no change in the behaviour of the fish. My drop checker is between green and yellow, so slightly up, but this has been like this for days. I did change some of the foam media in my filter that I use to diffuse the CO2. I added some very fine foam to it to diffuse the CO2 more efficiently. This was not checked as I did not turn down the CO2 nor have the chance to monitor the reaction of the fish this morning when the timer switched on the CO2 supply. Up until this morning they were acting as normal. My neons were glowing, swimming in the water flow or exploring. My clown loaches, despite only having two, were their usual playful selves and my guppies darting up and down, swimming low, medium and high in the tank and chasing each other. A very happy tank....
I am scrupiously careful to the point of obsessive when it comes to what goes in my tank; the buckets I use, how I dose anything and everything, how I clean various parts etc... Everything has it's place when not being used and nothing contaminates anything, nor does anything get contaminated by anything else in the house. My partner thinks I'm slightly disturbed when it comes to these matters and my children are ever so slightly afraid of me on Mondays...
Here's the crucial bit, which I think is to blame (unless it's the CO2). I had to replace the media in my U3 because when I bought the tank (second hand) the filter only came with the cartridges; no media supplied. When I did this weeks maintenance I noticed the Bio Max media was very smooth, not like the Bio Max I bought with my U2 for a previous tank, which is very gritty and rough. I still have my U2 and all parts so I took out the Bio Max to compare and sure enough the new Bio Max media I bought from Ebay was very different to the original. I decided to swap them over. They had been soaking in still water for around one month because I am selling my U2 along with a tank and other items. I thought by keeping the media wet I would be preserving healthy bacteria for the person buying my old kit. Nothing got into the media and I believed that keeping the media wet would preserve the bacteria within it.
It's the only thing I did differently and I am only glad that someone else didn't buy my stuff and then subsequently kill their fish. It's the only explanation I have...
The dead fish: The two clown loaches and guppies show no signs of any harm. Three of the five neons have bloated stomachs to the point they have ruptured, one especially so. The other two neons seem normal, except one of them is badly discoloured. From what I can see there are no other signs of distress in them, nor the other fish. See pictures (I flushed one of the clowns already but it was identical in physical appearance)
I have tested the main water parameters and now read ammonia 0, nitrite 1, nitrate 100. Nitrate at 100 after reading around 75 before a 50% water change and then reading 25 yesterday, just after the water change... Also nitrite at 1? I am puzzled at this.
My limited experience tells me a cloudy tank is due to a bacterial bloom; something that happens during a tank cycle? My tank was well cycled though. The Salifert nitrite test always came up slightly pink from the side view of the test tube every week, but analysis showed this to be around 0.025. The last test I did had clear water meaning there was absolutely 0 nitrite. Ammonia has always tested 0 since the cycle finished.
I'm not sure what to do really. Should I take the survivors out and completely clean the tank, or just 90% water change and see what happens? Have I had some sort of mad spike happen in one day? Was it the CO2's more efficient diffusion. A bit lost really. Lost and a bit devistated.....
Just to add. The remaining fish: 1 guppie and 3 neons appear to be completely fine. The neons are a little jumpy, but can't blame them for that. The guppie is acting like nothing happened...
I have a 125l Fluval Roma with U3 filter and two Chinese filters. CO2, EI dosing with salts and trace elements. My weekly 50% water change was due yesterday, which I did using Prime at .3mm per 12l bucket. Before the change my nitrates were somewhere between 50 and 100. After the change they were 25. Before the water change my tank was cycled, 0 on ammonia and nitrite. I use Salifert to test these particular parameters. As well as the water change I clean my filters on Mondays, using old tank water and this week I did a massive clean up. I took all my rocks out and scrubbed them with the tooth brush I use for this. Took all my plants out and gave them a clean, removing dead and dying leaves. I've been having problems with plant growth and this was part of the remedy required to improve on this. Nothing came into contact with anything it shouldn't have. This I am certain of.
I did increase my CO2 last week, but for some days there has been no change in the behaviour of the fish. My drop checker is between green and yellow, so slightly up, but this has been like this for days. I did change some of the foam media in my filter that I use to diffuse the CO2. I added some very fine foam to it to diffuse the CO2 more efficiently. This was not checked as I did not turn down the CO2 nor have the chance to monitor the reaction of the fish this morning when the timer switched on the CO2 supply. Up until this morning they were acting as normal. My neons were glowing, swimming in the water flow or exploring. My clown loaches, despite only having two, were their usual playful selves and my guppies darting up and down, swimming low, medium and high in the tank and chasing each other. A very happy tank....
I am scrupiously careful to the point of obsessive when it comes to what goes in my tank; the buckets I use, how I dose anything and everything, how I clean various parts etc... Everything has it's place when not being used and nothing contaminates anything, nor does anything get contaminated by anything else in the house. My partner thinks I'm slightly disturbed when it comes to these matters and my children are ever so slightly afraid of me on Mondays...
Here's the crucial bit, which I think is to blame (unless it's the CO2). I had to replace the media in my U3 because when I bought the tank (second hand) the filter only came with the cartridges; no media supplied. When I did this weeks maintenance I noticed the Bio Max media was very smooth, not like the Bio Max I bought with my U2 for a previous tank, which is very gritty and rough. I still have my U2 and all parts so I took out the Bio Max to compare and sure enough the new Bio Max media I bought from Ebay was very different to the original. I decided to swap them over. They had been soaking in still water for around one month because I am selling my U2 along with a tank and other items. I thought by keeping the media wet I would be preserving healthy bacteria for the person buying my old kit. Nothing got into the media and I believed that keeping the media wet would preserve the bacteria within it.
It's the only thing I did differently and I am only glad that someone else didn't buy my stuff and then subsequently kill their fish. It's the only explanation I have...
The dead fish: The two clown loaches and guppies show no signs of any harm. Three of the five neons have bloated stomachs to the point they have ruptured, one especially so. The other two neons seem normal, except one of them is badly discoloured. From what I can see there are no other signs of distress in them, nor the other fish. See pictures (I flushed one of the clowns already but it was identical in physical appearance)
I have tested the main water parameters and now read ammonia 0, nitrite 1, nitrate 100. Nitrate at 100 after reading around 75 before a 50% water change and then reading 25 yesterday, just after the water change... Also nitrite at 1? I am puzzled at this.
My limited experience tells me a cloudy tank is due to a bacterial bloom; something that happens during a tank cycle? My tank was well cycled though. The Salifert nitrite test always came up slightly pink from the side view of the test tube every week, but analysis showed this to be around 0.025. The last test I did had clear water meaning there was absolutely 0 nitrite. Ammonia has always tested 0 since the cycle finished.
I'm not sure what to do really. Should I take the survivors out and completely clean the tank, or just 90% water change and see what happens? Have I had some sort of mad spike happen in one day? Was it the CO2's more efficient diffusion. A bit lost really. Lost and a bit devistated.....
Just to add. The remaining fish: 1 guppie and 3 neons appear to be completely fine. The neons are a little jumpy, but can't blame them for that. The guppie is acting like nothing happened...