6 New Zebra Danios, 3 dead, one not swimming well

[flipperfeet]

Oh, I also put in some lifeguard for preventative measures. I'm hoping since most of the chemicals are gone that I can start.

They also appear to be playing... It fighting. But probably playing. Progress? Do dying fish play?

Dying fish absolutely do not play one last game of tag. One of the charms of danios is their playful schooling so this is progress.

 

[flipperfeet]

Would they all expire at nearly the same time if sick?

Note: I'm interested in learning, not trying to be contrary

Excellent question! Rarely, and not within minutes of each other. Another proof point for group exposure to a toxin.

 

[Eejaybee56]

Hello I am new to fish keeping. I purchased a 20 gallon tall tank a few weeks ago. Today I bought 6 Danios and put them in. Within the first hour 2 we're dead. They were swimming with their nose to the surface and eventually sank down and didn't go back up. The third died the same way a few hours later.

The 4th one does sink and rest at the bottom while gasping. Another one sometimes swims slightly tilted. The last one is the only one that seems to be fine. For now.

For water parameters there is not ammonia or nitrites. Nitrates stand around 15ppm. Ph is around 7.4-7.6. Temp is 79F. I have a filter and it's at the highest setting because I don't have tubes for my air pump. The tank is also full of live plants.

Any idea why they keep dying?

unless its all you had in your fish house and nothing but, then I would say change all water and start checking the nitrAtes, as they are rather hardy fish normally. If you have other fishys in your tank, make sure they are all good tank mates. Also, have you properly prepared the tank, or just bought it Monday and got the fish Friday?.
Filter needs to establish.
Do you have a decent filter system?
is there enough airtion/water flow? or is it static.
Danios are normally one of the easiest to keep, so if your having probs with them, then you need to recheck everything you have done, and make sure youve done it right.

 

[Lexiih36]

unless its all you had in your fish house and nothing but, then I would say change all water and start checking the nitrAtes, as they are rather hardy fish normally. If you have other fishys in your tank, make sure they are all good tank mates. Also, have you properly prepared the tank, or just bought it Monday and got the fish Friday?.
Filter needs to establish.
Do you have a decent filter system?
is there enough airtion/water flow? or is it static.
Danios are normally one of the easiest to keep, so if your having probs with them, then you need to recheck everything you have done, and make sure youve done it right.

I've returned the Danios. Currently I only have the Harlequin Rasboras, which are doing ok. 2 died, but I determined that to be due to an ammonia spike, which could have come from the large water change.

The deaths were on 2 separate days over night.

I bought the tank a few weeks ago and let it cycle.

 

[Lexiih36]

Excellent question! Rarely, and not within minutes of each other. Another proof point for group exposure to a toxin.

Yeah it was an extremely high pH, probably mixed with the high temp.

 

[Essjay]

let it cycle.

How did you actually cycle the tank? The reason I'm asking is because many people think that cycling means letting the tank run and doing nothing else. This is OK for a plant cycle where the tank is heavily planted with fast growing plants and then we wait until the plants are actively growing before getting fish, but with no live plants, or just a few slow growing plants, we need to add ammonia to grow the beneficial bacteria. Adding a bottle of bacteria without also adding ammonia won't cycle a tank.

due to an ammonia spike, which could have come from the large water change.

Water changes should not cause an ammonia spike; water changes are done to reduce ammonia. Water changes can cause an ammonia spike is if there was a lot of ammonia in the new water or if water conditioner was not used and the chlorine/chloramine killed the bacteria in a newly cycled tank before the biofilm has had chance to grow properly. Does your tap water contain ammonia?

 

[cmarbles]

How did you actually cycle the tank? The reason I'm asking is because many people think that cycling means letting the tank run and doing nothing else. This is OK for a plant cycle where the tank is heavily planted with fast growing plants and then we wait until the plants are actively growing before getting fish, but with no live plants, or just a few slow growing plants, we need to add ammonia to grow the beneficial bacteria. Adding a bottle of bacteria without also adding ammonia won't cycle a tank.



Water changes should not cause an ammonia spike; water changes are done to reduce ammonia. Water changes can cause an ammonia spike is if there was a lot of ammonia in the new water or if water conditioner was not used and the chlorine/chloramine killed the bacteria in a newly cycled tank before the biofilm has had chance to grow properly. Does your tap water contain ammonia?

I wish I'd made more effort to visit sites like this with helpful people like you before husband decided daughter could have fish. My response of "Fine, but it's up to you two, I've got enough to do" resulted in quite a few deaths. It was so upsetting for daughter (and me). Firstly, tank hadn't actually "cycled" (old school Dad thought just leaving it running with nothing in it, no food, no ammonia, did it). Secondly, we have ridiculously soft Yorkshire water so the platys and mollies gradually suffered. Anyway, long story short, I am now practually a BA Hons in fishkeeping and have taken over the whole thing because as a mother it is my job to keep everyone alive. (with the help of lots of test kits and some mineral additives).

 

[Lexiih36]

How did you actually cycle the tank? The reason I'm asking is because many people think that cycling means letting the tank run and doing nothing else. This is OK for a plant cycle where the tank is heavily planted with fast growing plants and then we wait until the plants are actively growing before getting fish, but with no live plants, or just a few slow growing plants, we need to add ammonia to grow the beneficial bacteria. Adding a bottle of bacteria without also adding ammonia won't cycle a tank.



Water changes should not cause an ammonia spike; water changes are done to reduce ammonia. Water changes can cause an ammonia spike is if there was a lot of ammonia in the new water or if water conditioner was not used and the chlorine/chloramine killed the bacteria in a newly cycled tank before the biofilm has had chance to grow properly. Does your tap water contain ammonia?

I added ammonia. The water change probably didn't cause the ammonia spike. But doing a 75% water change on the same day I got the fish probably did. While cycling, the ammonia levels peaked out at about 4.0ppm, nitrites got to I think 2ppm and nitrates got to 40ppm or more. Then it dropped. I added more, tested again a day later, and they went back to zero.

My tap water contains nitrates. I did a test of plain water after advice from here and found that out . I guess I said this on the other thread I opened, but essentially, on the day I bought the Danios, I tested the water like I usually do. I saw that the pH was really low, probably due to the driftwood. I wanted to raise it, so I went on the internet and saw a few recommendations to add baking soda to bring up the pH. I did that. That was a mistake because it bought it up to the high 8s. I didn't realize it because for some reason the water test was showing a mid to upper 7 pH, while the strip tests were showing a much higher reading.

Before I put the fish in, no nitrites or ammonia, but there was an elevated Nitrate level. After coming on here, someone suggested I do a 75% water change to get all the toxins out, so I did. I then did another 25% change the next morning. I imagine that definitely killed off some of the beneficial bacteria, and since it is still a newly cycled tank, combining the large water change with the sudden addition of 6 fish and food, it probably got overwhelmed. That's my running theory.

There was only 0.25 ppm of ammonia. Nitrites weren't elevated at all, and Nitrates are about 10-15ppm... I doubt it'll get lower, because my tap water has it.

 

[sparkypenguin]

Hi and sorry about your fish.

I would suggest going forward doing a frequent and regular set amount water change and letting the tank find it's "natural" PH level.
My newbie tank started out as 6.5PH but now that I do 7% per night, which works for me but I think most people do larger and less often changes, it's consistently 7.5PH.
The PH will be determined by the PH level of your tap water and everything that is in your tank, so remember that by adding fish, ornaments, chemicals etc you can potentially alter the PH, hence add / change things gradually.
If you carry out large water changes it can effect the PH quite significantly and fish as a rule do not like changing PH levels, even if the PH's are within that fishes preferred range. Of course large water changes as an emergency measure or if all of your tap water parameters are the same as your tank should be OK.
Also always use a de-chlorinator, like prime, however be aware that although prime will lower ammonia, nitrite and nitrate it's only a temporary lowering - check the instructions for more detailed info.
I would also start to carry out hardness checks on the KH and GH to establish these parameters.

Ideally all of your parameters should be fairly constant and you should always have zero ammonia and zero nitrites.
Once this has been achieved then you should have a good idea of what type of fish are going to enjoy your tank.
I would also establish what the tank parameters are of the shop.

Hope that helps.

 

[Oblio]

Before I put the fish in, no nitrites or ammonia, but there was an elevated Nitrate level. After coming on here, someone suggested I do a 75% water change to get all the toxins out, so I did. I then did another 25% change the next morning. I imagine that definitely killed off some of the beneficial bacteria, and since it is still a newly cycled tank, combining the large water change with the sudden addition of 6 fish and food, it probably got overwhelmed. That's my running theory.

99% of the BB lives in your filter media, substrate, tank walls, and decorations. As long as the fresh water does not have chlorine/chloramine, you will not harm the BB.

 

[Lexiih36]

Ok, so, there's no ammonia in the tank. If there was earlier, it's gone now. And it also turns out that my tap water actually does have a good amount of ammonia in it. At least .5 ppm. I just didn't see that cuz I used a strip test to test it and that test did not have an ammonia test.

 

[Nicky fish]

Hello I am new to fish keeping. I purchased a 20 gallon tall tank a few weeks ago. Today I bought 6 Danios and put them in. Within the first hour 2 we're dead. They were swimming with their nose to the surface and eventually sank down and didn't go back up. The third died the same way a few hours later.

The 4th one does sink and rest at the bottom while gasping. Another one sometimes swims slightly tilted. The last one is the only one that seems to be fine. For now.

For water parameters there is not ammonia or nitrites. Nitrates stand around 15ppm. Ph is around 7.4-7.6. Temp is 79F. I have a filter and it's at the highest setting because I don't have tubes for my air pump. The tank is also full of live plants.

Any idea why they keep dying?

Oh no I’ve been there! I lost a bucket load of fish to begin with. First thing was my filter broke not long after I inherited my fish from my daughter. When I replaced the filter I failed to realise that it needed to be acclimated with some of the good bacteria that already existed in the tank. Fish hate new stuff it affects the entire ecosystem - so that was my first mistake. Second mistake was buying fish that were kind of dodgy anyway tbh. So they basically all died, save for a very robust rainbow shark and very grumpy catfish. Oh wow I feel your pain tho! It’s such a journey. I ended up going to a proper aquarium (not petshop) to get some education. Since then everything has been perfect. I recommend going to your local aquarium. Fishy people are generally hugely passionate about fish keeping so then you will learn exactly what they need - not just what they want to sell you! Good luck

 

[Byron]

Ok, so, there's no ammonia in the tank. If there was earlier, it's gone now. And it also turns out that my tap water actually does have a good amount of ammonia in it. At least .5 ppm. I just didn't see that cuz I used a strip test to test it and that test did not have an ammonia test.

The ammonia in the tap water is likely because the water authority adds chloramine (instead of just chlorine).