Bought New Fish, Now All My Fish Are Dying

[corradophil]

I'm losing about 3 or 4 fish a day, there won't be any by the end of the week at this rate

Tank details:

Juwel Rio 125
Juwel internal filter as supplied with the tank
Argos childrens playsand substrate
Heavily planted with live plants
Standard T8 lights
No C02 injection
600 litres per hour Juwel pump, with outlet pipe pointing up for good surface movement.
Juwel water heater in filter box

Water details:

Temperature 25 - 26 deg C.
Ammonia 0
Nitrite 0
Nitrate 40ppm
PH 7.6

30 litre water change once per week using tap water from cold kitchen tap, treated with tetra aquasafe. Sponges lightly squeezed in siphoned old tank water to keep flow up. I usually only do 1 or 2 sponges at a time.

The Nitrate level of my tap water is around 40ppm.

History of tank:

The tank has been running for about 2 years as a freshwater tropical community tank. and for the last year has been running as described above without any major problems.

The stock until a week ago was, 1 boesemani rainbow fish, 1 Ancistrus, 1 Black Neon, 5 Cardinal Tetra, 2 Whiptails, 6 Zebra loach, A few Amano and Cherry Shrimps, Hitchhiker snails.

Last weekend I bought 4 Black Neons, 5 Cardinal Tetras and 4 Panda Cories.

The new fish were left for 15 mins in there bags floating in the top of the tank, and then put into the tank using a net to ensure very minimal amounts of the water from the shop got into the tank.

All was well for about a day, and then I noticed 1 Panda Cory had an eye missing, later that day he was nowhere to be seen. Then I noticed a Cardinal Tetra dead, which I removed, then a black neon, and so it went on. The 2 year old Ancistrus died suddenly, then more Cardinal Tetras, more Black Neons, all of which have been removed.

This morning I removed the last Cardinal Tetra, 1 Panda Cory and 1 whiptail, so not only are the new fish dying, but now all my previous established fish are dying.

Some of the Cardinal Tetras had swollen eyes, suggesting a Bacterial infection. Yesterday I treated the tank with medication for bacterial infection.

The LFS where I bought the fish checked my tank water and confirmed my test results are correct. They suggested that there is no way Cardinal Tetras would survive in water with a ph around 7.6, and Nitrate at 40ppm is not acceptable either, therefore my tap water is unsuitable for these fish.

I left the shop with 3 options:

1. Use only RO water from now.
2. Treat the tap water to adjust ph and lower Nitrate (I am not prepared to do this as the levels will be fluctuating and I'll be forever testing the water).
3. Keep different fish.

Whilst I understand my water stats are not perfect, the fish I had were fine until I introduced more, so I am not convinced the PH and Nitrate levels are the problem.

What should I do now? Leave the meds to work, do lots of massive water changes? Use RO water?

 

[Lolly123]

Hi,

Sorry to hear about your troubles. Im sure someone who is very knowledgeable about disease will comment soon enough. Until then I thought I'd give my two pennies.

The first thing I noticed, you are still running an internal filter, which in my opinion are not really that efficient. I have a feeling that your filtration might lack running on the internal alone, I would urge you to get an external filter, they can be expensive I know, but for the long run in cost efficiency and reliability you will get your money back.

I have a planted tank, no co2 either, and although it is debateable, I put my airstone on a gentle stream at night to prevent the o2 from dropping over night. Im not saying its imperative, but seeing as you dont inject co2 and you are heavily planted, it might be beneficial.

You said that you acclimatised by floating them for 15 and then putting them in the tank, well first you should add some of your tank water, you can use different methods such as the drip method, but I would say it is very important to expose your new fish to your water parameters slowly before netting them and putting them straight in.

Some people do small water changes with cold water but tbh i think it's a better habit to try and temperature match your new water to that of your tank as best as you can.

As for nitrate, I would highly doubt that that is the reason for your troubles, 40ppm isnt really much to be alarming about. Although very high persistent nitrates can cause issues to your fish especially young ones, I would say that your nitrate levels would have to be persistently higher than 40ppm to start causing big issues. What are your nitrate levels straight from your tap?

My mother keeps cardinal tetras in her planted aquarium, and we have a pH of 7.8, of course Id like to be able lower that slightly as 7.8 is higher than id like to have, but our tetras are doing good and always have done. I would much rather a stable pH slightly on the high side rather than constant pH swings, which isnt good at all.

Even though you say the tank has been running for two years, id say that adding 13 fish at once isnt a good idea, thats going to be quite a load for your filter to contend with, especially a small internal one.

As for the disease, I'll leave that to someone who can give you better advice, but overall if your water quality isnt as good as it should be and stress isnt minimised in some of the ways mentioned above, your fish will be more susceptible to picking up disease, thus spreading to other inhabitants and consequently wiping out your stock.

Lastly, what test kit do you use?

 

[corradophil]

Hi Lolly123, thanks for your reply. I understand what you are saying about the filter, but I would have thought high ammonia and nitrite levels would be evedent if it was not keeping up?

I'll up the levels of surface movement more, to try and introduce more oxygen

Your comments on Nitrate and PH are encouraging, and as I have successfully been keeping these types of fish since I had the tank, I have my doubts that these are the cause of the problem.

It sounds like my biggest mistake was adding too many fish at once, and not introducing them correctly, causing stress, which allowed infection to develop, and then spread to the other previously healthy fish.

My test kit is an ABI one. The results that the LFS got matched mine, so I guess this is ok.

So now my mission is to save the remaining fish. What is my best course of action to do this.

I really do not want to see any more fish suffer and die.

 

[Lolly123]

Hi Lolly123, thanks for your reply. I understand what you are saying about the filter, but I would have thought high ammonia and nitrite levels would be evedent if it was not keeping up?

I'll up the levels of surface movement more, to try and introduce more oxygen

Your comments on Nitrate and PH are encouraging, and as I have successfully been keeping these types of fish since I had the tank, I have my doubts that these are the cause of the problem.

It sounds like my biggest mistake was adding too many fish at once, and not introducing them correctly, causing stress, which allowed infection to develop, and then spread to the other previously healthy fish.

My test kit is an ABI one. The results that the LFS got matched mine, so I guess this is ok.

So now my mission is to save the remaining fish. What is my best course of action to do this.

I really do not want to see any more fish suffer and die.

Yes I would say that, if you've got an api test kit, which are good, and you've been testing regularly for ammonia and nitrite and it shows consistently zero, then I assume that would be reliable, because I believe my liquid test kit when it tells me that I guess the difference in my canister filter is that ive got quite substantial media in there that has quite a large surface area, allowing the baceria to colonize very well. I think if you're satisfied with your internal and its not contributing to any water quality fluctuations then I'd say see how it goes. But just as a general recommendation, i'd say if your purse strings allow at some point in time, try a good canister, you wont be disappointed, but of course its up to you

PH and nitrate are obviously things to keep a close eye on, but as stated before my fish are doing good in 7.8. I am just very meticiulous about my water changes, ensuring a very good gravel twice a week, as my tank has some big fish that produce a lot of waste, and I also have plants, so I pay alot of attention ensuring there are no rotting leaves etc lurking under the gravel.

As for the disease, I guess it is very possible that you either introduced a new fish that was carrying something, or already had an unwell fish. I would recommend keeping a very good eye on your water quality, keeping it top notch. I read that eye bulging is a symptom of an underlying infection but I'll leave the possible diagnoses to someone else on here as I dont want to tell you rubbish. I guess you didnt have the option to remove the diseased looking fish to a hospital tank, I dont have a hospital tank anymore, but they can be life savers, good things to have.

There is someone on here called wilder who seems to know a lot about fish diseases from what i have observed, he or she may be able to help you with administering meds and a course of action from here on out.

One other thing I can think of to help prevent future out breaks of disease apart from good tank/water maintainence is a UV sterilizer. I used one on my marine tank, they are said to help reduce water borne bacteria. Im not saying you need one, but just giving a little info as I had quite good results from mine.

I hope you solve your problems and im sure someone else will come to the rescue in regards to meds and stuff.

 

[Athena]

Hi - sorry to read about your recent problems.

When you did your water test was it before/after a water change?

I think it probably was a case of adding too many fish in one go - there would more than likely have been a spike of toxins, plus the fish would have been stressed from the move and very short acclimatisation period. Stress alone can cause fish to die suddenly, or cause bacterial disease to flare up.

Panda cories are very sensitive little fish who have a reputation for dying off within days of entering their new tank.

Also, are you sure you weren't overstocked? Seems a fair few fish in a 125litre to me.

If any of your remaining fish are showing signs of bacterial disease, such as pop eye, you can treat with an anti-bac medication, such as Myxazin, which I found to be excellent treatment when one of my sailfin mollies had popeye some years ago.

Regards - Athena

 

[corradophil]

The water test was carried out before a water change.

I'll have a look into stock levels, but was under the impression that it was about right, although at the upper levels.

I will also have a read up on UV sterilizers.

When I got home from work last night, I found the last two Black Neons dead floating at the top of the tank

I removed them, and took the decision that bacteria would be in the water, so a big water change would at least reduce the bacteria in the tank. I took out about 90 litres in the end, and refilled it keeping an eye on the temperature. To increase the temperature I boiled water in the kettle and added it to the water in the bucket.

So far so good. This morning all the fish were alive and looking well.

I think I will continue doing water changes once a day for the rest of the week, although I'll just do 30 litre ones from now on. Hopefully, this will reduce the bacteria level enough to solve the problem.

 

[Lolly123]

The water test was carried out before a water change.

I'll have a look into stock levels, but was under the impression that it was about right, although at the upper levels.

I will also have a read up on UV sterilizers.

When I got home from work last night, I found the last two Black Neons dead floating at the top of the tank

I removed them, and took the decision that bacteria would be in the water, so a big water change would at least reduce the bacteria in the tank. I took out about 90 litres in the end, and refilled it keeping an eye on the temperature. To increase the temperature I boiled water in the kettle and added it to the water in the bucket.

So far so good. This morning all the fish were alive and looking well.

I think I will continue doing water changes once a day for the rest of the week, although I'll just do 30 litre ones from now on. Hopefully, this will reduce the bacteria level enough to solve the problem.

As far as im concerned water changes are a good thing. Keep it up and monitor the health of your fish very closely. But I guess if your problem still persists you probably will have to treat the tank with some meds as Athena mentioned. But lets hope this will be the end of your fish loss.

Im sure if you keep up the hard work on your tank you will see an improvement.

As for stocking, id say you were aiming a little high in regards to how many fish you could have but I guess most of us are a little guilty of this at one point or another.

Let us know how you get on in the upcoming days. Wish you luck.

 

[elisew]

Big water changes will benefit the whole tank so good stuff that you`re doing them

Would you by any chance have plants in the tank that may not be proper aquatic plants? I only ask because I too had a problem with lots of fish dying, despite API test results being spot on......it turned out that some of the plants that had been sold to me as aquatic plants, actually weren`t aquatic plants at all. It`s the only conclusion that was dealt with and hey presto my fish and other plants have been happy and healthy ever since.

Could you maybe post a pic of your tank just in case there`s a plant or 2 that might be causing a problem?

 

[corradophil]

Thanks for the replies.

I'll carry on with the water changes and see how it goes. If I lose more fish I'll go for the meds route.

I have Java Ferns, Anubias and cryptocoryne balansae.

When I was getting into planted tanks, I went through loads plants sold as aquatic, which turned out not to be. In the end I based by plant choice on one of George Farmer's tank setups. Now all proper aquatic plants.

 

[corradophil]

No deaths yesterday.

I did another water change last night, this time 30 litres.

Here's a pic of the tank last night.

By the way, the CO2 injection equipment is not in use at the moment, but will be soon.

 

[Lolly123]

No deaths yesterday.

I did another water change last night, this time 30 litres.

Here's a pic of the tank last night.

By the way, the CO2 injection equipment is not in use at the moment, but will be soon.

Looks like you're doing a good job, tank looks nice and clean and well maintained.
Anubias looks lovely, very nice plant indeed and am also glad to hear your fish are still with you

 

[corradophil]

Looks like you're doing a good job, tank looks nice and clean and well maintained.
Anubias looks lovely, very nice plant indeed and am also glad to hear your fish are still with you

Thanks just need to get the cryptocoryne balansae to establish itself now. I did have Valis, but have removed it in favour of this. My CO2 system is all set up, just need to get the extinguisher refilled.

 

[Lolly123]

Looks like you're doing a good job, tank looks nice and clean and well maintained.
Anubias looks lovely, very nice plant indeed and am also glad to hear your fish are still with you

Thanks just need to get the cryptocoryne balansae to establish itself now. I did have Valis, but have removed it in favour of this. My CO2 system is all set up, just need to get the extinguisher refilled.

I have a planted tank and tried a diy setup once, but it was too unstable as my tank was quite large. I do have some trouble with some of the plants in my tank right now. I know really that the key to good plants is working out what you want and establishing lighting, nutrients and co2 requirements. But it's hard to fix it all right now with no money to do so. But I really really want green lush plants that grow well. Oh well...that job im waiting for better get back to me soon But if I earn too much, ill be tempted to go back to marine...

Anyway best of luck with your tank. It's nice to see people putting effort into their little habitats!