Harlequin rasbora die off

[Fray]

Hi, I don't know whether this would be classed as an emergency because I've just about given up!

Bought 15 harlequins from lfs on the 15/7 to bump up my school of 6. Put them straight into 20l qt which I've kept cycled. As of now I'm down to 3, and have more grey hairs to show for it.
Harlies become still, then flip over and lie on bottom. Swim around a bit then do it all over again, till they just seem to give in and lie there. They didn't die all at once, it was spread out over the time I have had them. Just enough to give me hope they may survive. No physical signs of anything wrong with dead ones. After 2nd death I dosed with worming meds.

Have bought most of my fish from same lfs, with never a problem. Tho I did notice a gourami with ick that was in a mixed tank for at least two weeks with nothing done. Have not bought from there since seeing that, apart from last harlies, which I had ordered in. They had not been long in store, could stress be the cause?

20l cycled qt
Ammonia 0
Nitrite 0
Nitrate between 10 and 15
Temp 24
Ph 7.4 tested one day and it had gone up to nearly 8.0 (???) so I supplemented tank water with tap water (conditioned) and test daily after
GH of my area is appox 100
Small sponge filter
Air stone
Floating live plants plus 1 fake one
pvc pipe hide

I've hardened myself to losing the remaining three, who seem fine now but so did the others till they did the flip and die, would love any insight on what might have happened?

So disheartening......

 

[itiwhetu]

Too many fish for a 20 Liter, are you sure of your ammonia, nitrite readings? Is this tank planted? Harlequins love plants.

 

[Colin_T]

If fish are dying, it is an emergency.

How long have you had the new harlequin rasboras for?
How long had the shop had them for before you got them?
What is the pH of the water at the shop?

How often are you doing water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the tank?

When was the filter cleaned last?
How did you clean the filter?

What medication did you use to deworm the fish?
Did you do a water change after deworming the fish?

------------------
Pictures and video of the fish and the entire tank. Try to get some of the fish doing weird stuff. If you use a mobile phone to film them, hold the phone horizontally so the footage fills the entire screen. Upload videos to YouTube, then copy & paste the link/s here. Make videos about 1 minute long, or longer if the fish is acting weird for longer.

Check pictures on a computer and make sure they are in focus.

------------------
If the fish had only come into the store in the last few days, and they came from water that had a different chemistry (pH, GH & KH) to the shop and your tank, then it is possible the fish are suffering from too many or too sudden a change in water chemistry. If this is the case, the best thing to do is no water changes for 2 weeks, then only small 10% water changes a couple of times a week. Do these 10% water changes for a few weeks and see how the fish go. If the fish settle down and no more die with the small water changes, you can try doing a bigger one (20%) and see if they are ok. But keep the water changes small until the fish have been in the tank for at least a month or two.

A similar issue can occur if the shop did a water change on the day you bought them. The fish get exposed to too many different changes in water chemistry and it knocks them about really badly. Then they die over the next few weeks. Any sudden shock like lights coming on or going off, people walking past the tank suddenly and unexpectedly, or someone tapping on the tank can be enough to cause them to go into shock, roll over and die right in front of your eyes.

------------------
Maybe contact the shop and let them know you are having trouble with the fish and most have died. Ask them when they do water changes and when they got the fish in. See if they had any problems with the fish.

As a general rule, if you are getting fish, try to buy them on the day before they get a water change, or the day of the water change but before anyone has cleaned the tank. That way the fish should have had a week or so to adapt to the new water in the shop tank.

Try not to buy fish that have just come into the shop. Wait a week and then buy them. Try to get fish on the day before new fish come in and get added to the tanks. This gives the fish a chance to recover from being shipped to the shop and put into water with a potentially different water chemistry.

The following link tells the story about what tropical fish go through to get from the fish farm to the shop. I might interest you. Fish go through a lot of stress and it can definitely kill them.

Fish Importing, from the farm to the home

If any of you have wondered how aquarium fish get to the local pet shop, the following will give you some insight as to what they have to go through to get from the fish farm where they are bred and raised, to the pet shop where you can buy them. The stress they go through is quite...

www.fishforums.net

 

[Fray]

Thanks for your reply, So...

Got them 15/7
Straight into qt
Lfs had them 6 days, I picked them up 3 days later
Ph lfs 7.4 supposedly
Water changes daily, approx 15%
Lfs does water changes weekly, Sat, I got them following Friday
No substrate
New water de chlorinated
Filter cleaned in tank water yesterday, before that 7 days previously
Fluke and tapeworm med Blue Planet
Waited a day before wc as per instructions

I didn't want to leave them at lfs for too long because of ick problem I saw in another tank previously. So maybe I got them too quickly.
Thanks for link.

 

[Fray]

Too many fish for a 20 Liter, are you sure of your ammonia, nitrite readings? Is this tank planted? Harlequins love plants.

This is just a quarantine tank, and have floating live plants. Tank is cycled, and readings are right

 

[itiwhetu]

This is just a quarantine tank, and have floating live plants. Tank is cycled, and readings are right

I think you have to many fish in the tank

 

[Fray]

I think you have to many fish in the tank

Ok, but for last week the number of fish has been dropping, with only three left today, and still no change. So say four days ago there were seven fish, with daily water changes and still deaths occurring? I'm constantly monitoring tank and just cant understand. Surely that is not too many fish with daily wc?

 

[Fray]

If fish are dying, it is an emergency.

How long have you had the new harlequin rasboras for?
How long had the shop had them for before you got them?
What is the pH of the water at the shop?

How often are you doing water changes and how much do you change?
Do you gravel clean the substrate when you do a water change?
Do you dechlorinate the new water before adding it to the tank?

When was the filter cleaned last?
How did you clean the filter?

What medication did you use to deworm the fish?
Did you do a water change after deworming the fish?

------------------
Pictures and video of the fish and the entire tank. Try to get some of the fish doing weird stuff. If you use a mobile phone to film them, hold the phone horizontally so the footage fills the entire screen. Upload videos to YouTube, then copy & paste the link/s here. Make videos about 1 minute long, or longer if the fish is acting weird for longer.

Check pictures on a computer and make sure they are in focus.

------------------
If the fish had only come into the store in the last few days, and they came from water that had a different chemistry (pH, GH & KH) to the shop and your tank, then it is possible the fish are suffering from too many or too sudden a change in water chemistry. If this is the case, the best thing to do is no water changes for 2 weeks, then only small 10% water changes a couple of times a week. Do these 10% water changes for a few weeks and see how the fish go. If the fish settle down and no more die with the small water changes, you can try doing a bigger one (20%) and see if they are ok. But keep the water changes small until the fish have been in the tank for at least a month or two.

A similar issue can occur if the shop did a water change on the day you bought them. The fish get exposed to too many different changes in water chemistry and it knocks them about really badly. Then they die over the next few weeks. Any sudden shock like lights coming on or going off, people walking past the tank suddenly and unexpectedly, or someone tapping on the tank can be enough to cause them to go into shock, roll over and die right in front of your eyes.

------------------
Maybe contact the shop and let them know you are having trouble with the fish and most have died. Ask them when they do water changes and when they got the fish in. See if they had any problems with the fish.

As a general rule, if you are getting fish, try to buy them on the day before they get a water change, or the day of the water change but before anyone has cleaned the tank. That way the fish should have had a week or so to adapt to the new water in the shop tank.

Try not to buy fish that have just come into the shop. Wait a week and then buy them. Try to get fish on the day before new fish come in and get added to the tanks. This gives the fish a chance to recover from being shipped to the shop and put into water with a potentially different water chemistry.

The following link tells the story about what tropical fish go through to get from the fish farm to the shop. I might interest you. Fish go through a lot of stress and it can definitely kill them.

Fish Importing, from the farm to the home

If any of you have wondered how aquarium fish get to the local pet shop, the following will give you some insight as to what they have to go through to get from the fish farm where they are bred and raised, to the pet shop where you can buy them. The stress they go through is quite...

www.fishforums.net

After reading that I wonder that any fish survive. Also makes me feel guilty for even perpetuating the trade. I've bred my swordtails and cories, and given them away to local fish lovers, and my six harlies are thriving, but now I'm wary of buying anything more!. Thanks for your help

 

[Colin_T]

If you don't have any ammonia or nitrite in the quarantine tank, stop water changes for a week.

Post pictures and video of the fish

Put a thin layer of substrate (sand or gravel) on the bottom of their tank. It only has to be thick enough to stop them seeing the glass.

Have a picture on the back of the tank if you don't have one already.

------------------
Are the fish eating well?
What does their poop look like?

 

[Fray]

Ha, you read my mind, just put a thin layer of sand on bottom of tank. Don't have back of tank picture but have towel there to soak up any excess moisture. They are eating well, unless they have started the stop and die thing, Hard to see their poop, must be very little. Have been alternating between flakes, normal and spirulina, crushed, live mozzie larvae, and micro guppy food.
Don't have pics of sick fish, will try if remaining ones go downhill.
Will stop water changes for now, hopefully I havent been making things worse with those.
Thanks once again for help

 

[GaryE]

I'm thinking quarantine was a good idea!

The QT tank is small, and that doesn't help, but 8 days in... you can't blame the store, as these things surprise them too. Bacterial, viral, you may never know.

 

[Fray]

I'm thinking quarantine was a good idea!

The QT tank is small, and that doesn't help, but 8 days in... you can't blame the store, as these things surprise them too. Bacterial, viral, you may never know.

Thanks, I'll have to invest in a larger qt. But I usually don't have such a large quantity of fish to quarantine. That's on me.
Live and learn

 

[Fray]

I'm thinking quarantine was a good idea!

The QT tank is small, and that doesn't help, but 8 days in... you can't blame the store, as these things surprise them too. Bacterial, viral, you may never know.

Do you think a 10 gallon enough for qt? If so, how many fish at a time could I safely quarantine?