This tropical fish hobby can be a hard watch

[Country joe]

I recently completed a fishless cycle, test results were good, two days ago I put in 10 Harlequin Rasboras and 10 Green Neon Tetras, the next day I noticed one of the Harlequins being on its own and swimming up and down, and this morning it's lying at the bottom of the tank still alive but not moving, I did a water test .ammonia 0, nitrite, 0 and PH 8, today I've noticed another Harlequin on its own doing the same thing, swimming up and down, and not mixing with his tank mates, the rest of the Harlequins and The Tetras appear fine. I took aquarium water to my local fish store,not PAH, to be tested and they came up the same as mine, all good, when I purchased the fish they were put in the tank, the way the experts advise, and aquarium lights off, and also tempature is good.
Could it be stress ? It's a 125 litre tank.

 

[Colin_T]

Pictures and video of the fish?
Upload videos to YouTube, then copy & paste the link here.
If you use a mobile phone to film the fish, hold the phone horizontally (landscape mode) so the footage fills the entire screen.

 

[Country joe]

Sorry Colin can't do it I'm useless on the internet



N

 

[10 Tanks]

Hello. That's an awful lot of fish to put into a tank all at once. Generally, you add a few and see how they do. 30 gallons of water isn't very much. So, just a few, small fish is enough. You change half the tank water every few days for a few weeks and to be on the safe side, dose a bacteria starter when you change the water. The water change will remove the dissolving fish waste material and the bacteria starter will use what nitrogen is left in the tank. After a month or so, when the water change and bacteria routine is established, you can add a few more small fish. You can never, ever over populate a tank. You won't be able to keep up with the removal of waste material from a large number of fish.

10

 

[Country joe]

I thought when I putting in 80 drops of ammonia at the end of the cycle, and after 24 hrs the tank results were good you could add fish ,the Green Neon Tetras are small., if I was to do what you said I would have to send away for dr tims bacteria, don't know how long it would come by post, especially with tomorrow being a may day holiday, no post, I did a 25% waterchange, the day before I added the fish.

 

[Essjay]

Country joe has done a fishless cycle not a fish-in cycle.

The whole idea of fishless cycling is to grow more bacteria that a tankful of fish need so that all the intended fish can be added as soon as the cycle has completed.
From the fishless cycling guide on here

A major benefit of this fishless cycling method is that you can now fully stock your tank in one go. This means an average stocking level for your tank size. It certainly does not mean you can stock heavily or over stock. If for any reason you are unable to stock the tank when it is cycled, you can continue adding ammonia to keep the tank cycled.

 

[FishyD]

I recently completed a fishless cycle, test results were good, two days ago I put in 10 Harlequin Rasboras and 10 Green Neon Tetras, the next day I noticed one of the Harlequins being on its own and swimming up and down, and this morning it's lying at the bottom of the tank still alive but not moving, I did a water test .ammonia 0, nitrite, 0 and PH 8, today I've noticed another Harlequin on its own doing the same thing, swimming up and down, and not mixing with his tank mates, the rest of the Harlequins and The Tetras appear fine. I took aquarium water to my local fish store,not PAH, to be tested and they came up the same as mine, all good, when I purchased the fish they were put in the tank, the way the experts advise, and aquarium lights off, and also tempature is good.
Could it be stress ? It's a 125 litre tank.

Stress can definitely be a factor. We rarely know the history of out fish unless you are buying from a trusted local breeder. In just the past few weeks your fish may have traveled a few thousand miles, changed hands from a grower to a wholesaler to an LFS to your tank. A few can be sick for weeks before symptoms even appear. As fish keepers all we can really do is provide a clean and properly prepared home, a gentle as possible transition, an attempt to care for them when issues arise anyway. As you said it can be hard to watch at times. Especially at first. I have become much more religious about using my quarantine tank for new fish, because new community member puts the healthy fish you already have at some level of risk. I only have one LFS that I know quarantines new arrivals. That certainly helps, but nothing is foolproof. I am not saying your local source is bad, but over time you will discover quality options. It is also a very good idea to start with species known toi be more hardy. Rasboras aren't a terrible choice. I hope the neons go smoothly for you.

 

[Lcc86]

It may just be bad luck/bad genetics etc, but do some extra water changes over the next few days just in case. You've mentioned ammonia and nitrite above but not nitrate, have you checked that? Your pH is also quite high for the fish you have.

 

[Country joe]

Well the Harlequin. Was dead this morning,, but no more deaths, I plan to do a 25 % water change every Sunday, I last did one on Friday the 3rd of May, before I added the fish should I do another 25% water change today, or can it wait till Sunday.
Did a water test today.
Ammonia 0
Nitrite 0
Nitrate 0
PH 7.5.

 

[gwand]

Well the Harlequin. Was dead this morning,, but no more deaths, I plan to do a 25 % water change every Sunday, I last did one on Friday the 3rd of May, before I added the fish should I do another 25% water change today, or can it wait till Sunday.
Did a water test today.
Ammonia 0
Nitrite 0
Nitrate 0
PH 7.5.

If your A,N and N levels stay 0 it can wait.

 

[Lcc86]

Well the Harlequin. Was dead this morning,, but no more deaths, I plan to do a 25 % water change every Sunday, I last did one on Friday the 3rd of May, before I added the fish should I do another 25% water change today, or can it wait till Sunday.
Did a water test today.
Ammonia 0
Nitrite 0
Nitrate 0
PH 7.5.

While the levels are 0 you don't necessarily need to change but if youve had a death a water change may be helpful. 50% or higher is usually recommended as if you're only removing 25% you're leaving 75% of any existing ammonia etc.

 

[Country joe]

my ammonia has been nil for a while