Hi guys,
I've just 5 minutes ago lost my second fish in 3 weeks, so I thought it best to ask for some advice.
I had a 10g nano tank, which happily housed an ocellaris clownfish, magenta dottyback, and yellow clown goby, for 2 1/2 years. At the beginning of March this year, I moved house and also "upgraded" to a different tank; the same size, but a bit neater and with a built-in light. My fish survived the 1-hour journey absolutely fine, with the only potential issue being my magenta dottyback whose gills seemed to turn red after the first day, and stayed like that until he died, but other than that he's been just fine. All fish seemed to settle in to the new tank very well.
All of my new tank parameters have been the same as my old tank: 0 ammonia, 0 nitrite, 20-40 nitrates (I know this is high, and I'm trying to reduce it, but I don't have any corals/inverts in the tank), pH 8.2, SG 1.024. The only difference is the tank temp: the tank is in a poorly insulated part of the house at present until we get everything sorted, and has risen from ~25ºc (max 2° swing per day), to ~29.5°c with the recent hot weather we've had over the last couple of months. But, the temperature rises gradually, and never goes more than max 1.5° either side.
The first problem started 3 weeks ago with my clownfish when I was changing the filter media and doing a waterchange. I didn't expect any problems as this was the third time I'd done this exact same thing, which involves gently lifting some of my live rock so I can lift the filter up to replace the media, which inevitably stirs up some debris in the tank. This swirled around for a while and then settled back down when I put my filter back on, as usual. This time, after darting for my fingers in the tank as he has done for almost 3 years, and looking as alert as ever, I noticed him gulping at the surface. This was then followed by some quick "spasms" around the tank, banging into rock etc., lying upside down on the bottom, and then sadly dying. I was incredibly sad about this, as I put so much effort into the tank changeover and journey, and have had these fish in my previous tank, with no problems at all, for close to 3 years. However, I put it down to it "being his time", and possibly him gulping in too much of the "debris" when it was swirling round the tank after I disturbed the rock.
But, today, I was just doing a normal waterchange - not even a filter change, so no debris - as I always have done: SG/temp matched to tank, mixed in a bucket with a powerhead for a minimum of 24hours (this time it was mixing for 3 days), but straight afterwards, I noticed all fish were behaving strangely: both clown gobys (I now have a green clown goby also, which has been in there for a couple of months) were breathing heavily, which has now stopped. But, the main problem was with my dottyback, who straightaway was lying almost on his side at the bottom of the tank, breathing very heavily and with his mouth open. He moved positions approx. 30 mins later, and 20 mins after that, after a couple of spasms, is now dead.
I don't know what I'm doing wrong, other than the nitrates, as ammonia is 0 (I've tested on two kits) and all other levels seem fine. I do have quite a bit of green algae in the tank, which may be consuming a lot of oxygen, and also I understand that higher temperatures can reduce the oxygen level. But, why would both fish die straight after a waterchange? I don't understand.
Hoping for some advice?
I've just 5 minutes ago lost my second fish in 3 weeks, so I thought it best to ask for some advice.
I had a 10g nano tank, which happily housed an ocellaris clownfish, magenta dottyback, and yellow clown goby, for 2 1/2 years. At the beginning of March this year, I moved house and also "upgraded" to a different tank; the same size, but a bit neater and with a built-in light. My fish survived the 1-hour journey absolutely fine, with the only potential issue being my magenta dottyback whose gills seemed to turn red after the first day, and stayed like that until he died, but other than that he's been just fine. All fish seemed to settle in to the new tank very well.
All of my new tank parameters have been the same as my old tank: 0 ammonia, 0 nitrite, 20-40 nitrates (I know this is high, and I'm trying to reduce it, but I don't have any corals/inverts in the tank), pH 8.2, SG 1.024. The only difference is the tank temp: the tank is in a poorly insulated part of the house at present until we get everything sorted, and has risen from ~25ºc (max 2° swing per day), to ~29.5°c with the recent hot weather we've had over the last couple of months. But, the temperature rises gradually, and never goes more than max 1.5° either side.
The first problem started 3 weeks ago with my clownfish when I was changing the filter media and doing a waterchange. I didn't expect any problems as this was the third time I'd done this exact same thing, which involves gently lifting some of my live rock so I can lift the filter up to replace the media, which inevitably stirs up some debris in the tank. This swirled around for a while and then settled back down when I put my filter back on, as usual. This time, after darting for my fingers in the tank as he has done for almost 3 years, and looking as alert as ever, I noticed him gulping at the surface. This was then followed by some quick "spasms" around the tank, banging into rock etc., lying upside down on the bottom, and then sadly dying. I was incredibly sad about this, as I put so much effort into the tank changeover and journey, and have had these fish in my previous tank, with no problems at all, for close to 3 years. However, I put it down to it "being his time", and possibly him gulping in too much of the "debris" when it was swirling round the tank after I disturbed the rock.
But, today, I was just doing a normal waterchange - not even a filter change, so no debris - as I always have done: SG/temp matched to tank, mixed in a bucket with a powerhead for a minimum of 24hours (this time it was mixing for 3 days), but straight afterwards, I noticed all fish were behaving strangely: both clown gobys (I now have a green clown goby also, which has been in there for a couple of months) were breathing heavily, which has now stopped. But, the main problem was with my dottyback, who straightaway was lying almost on his side at the bottom of the tank, breathing very heavily and with his mouth open. He moved positions approx. 30 mins later, and 20 mins after that, after a couple of spasms, is now dead.
I don't know what I'm doing wrong, other than the nitrates, as ammonia is 0 (I've tested on two kits) and all other levels seem fine. I do have quite a bit of green algae in the tank, which may be consuming a lot of oxygen, and also I understand that higher temperatures can reduce the oxygen level. But, why would both fish die straight after a waterchange? I don't understand.
Hoping for some advice?