Why are my guppies dying?

[Flowerfairy13]

Tank info;
250 Litres/66 Gallons
3 years old.
Planted tank with sand
Temp constantly between 25-25.5 degrees Celsius
Water changes completed weekly. I also use Flourish, API Stress Coat & Seachem Prime when completing changes. I also have well water.
Fed 2 small meals a day, Fluval bug bites in morning & brine shrimp in evening (plus algae wafer for bristlenose)

Species;
Salt & Pepper Corys x 6, Bronze Corys x 8, Albino Corys x 6, Neon Tetra x 15, Guppies x 15, Swords x 3, Mollies x 8, Golden Bristlenose x 1, Pearl Gourami x 2, Bladder Snails, 3 Spot Red Snails, Nitrite Snails, Guppy Fry & Sword Fry. There are also a few shrimp, unsure of how many exactly as they keep themselves well hidden.

Parameters;
Ammonia – 0PPM
Nitrite – 0PPM
Nitrate – 60PPM
PH – 8.2
GH – 200-400PPM (21 drops in GH test kit)
KH – 100-200PPM (9 drops in KH Test kit)

HELP!!!!!! I have no idea why my guppies keep dying. About 2 weeks ago I lost my first guppy. She was around a year old and I found her floating in the tank one morning. I didn’t think too much of it as she was about 1.5 years old and had no obvious signs of infection or damage so I put it down to age. Since then, I have lost 9 more guppies in different circumstances and I can’t understand what’s happening. A few more died seemingly for no reason, one due to dropsy which seemed to come on over the space of a few hours. He was totally normal at feeding time in the morning, by the afternoon he had pineconed really dramatically and was bloated and struggling to swim. Another guppy today seems to be slightly bloated, hasn’t eaten this evening & her fins look shredded? Again, she was perfectly fine this morning, she ate and her fins were normal. I always pay particular attention to this guppy as she is my favourite, so I know 100% she was fine just this morning.

None of these guppies are from the same bloodline to my knowledge, I have not bred them myself but they have come from different stores.

Nothing has changed in my tank over the past few weeks, I haven’t added more plants, haven’t changed foods, products or anything like that.

I did add 3 new Guppies & 6 new corys last thursday but I don't think this has anything to do with it as the Guppies started dying before then. The only thing I have done differently in the past month that I have never done before is give them live food once. I ordered some live brine shrimp from a fish store and fed them to the tank. I rinsed the shrimp before I fed them, I didnt just tip the salty water straight in so I really don't think that has anything to do with it either?

2 weeks ago my Gouramis did start acting strange, they were chasing each other and nipping each other. I never saw them nipping anything other than each other, and they have stopped now so I am not sure that is an issue either.

There was an incident a few weeks go where my daughter overfed them, by the time I had gotten the net to scoop the excess out of the tank the guppies had quite a feed. Could this be causing my problem? Could they have overindulged and now having intestinal problems?

Everyone in the tank is behaving normally, even the guppies. Aside from that one who had dropsy, all of the others appeared totally normal until they died.. All of the fry in the tank are doing really well and to my knowledge I haven’t lost any of them. I would assume they would suffer first if their was a problem with the tank?

Is it just a coincidence that I have lost so many in the last few weeks? I really don’t know what’s happening but I don’t want to lose anymore!!

Also – any tips on what to do with my poor girl with the shredded fins? Should I wait a few more days and see if she eats? Or should I PTS?

Thank you so much in advance!!


​

 

[emeraldking]

There could be multiple reasons why your guppies have died. Even if the water parameters are okay, there could still be something infectious where those guppies are sensitive to. But in that case, the water should be checked under a microscope. But be also aware that commercial guppies (especially those form Asian fish farms) are prone to disease, worms or even parasites. And even if you would buy those guppies at different stores, they can still come from the same wholesaler.

 

[AdoraBelle Dearheart]

Can you grab some photos of the tank and fish, please? It sounds pretty heavily stocked and nitrates are high, and you've been adding new stock which adds to the bioload, and without QT, which means diseases/worms etc are easily introduced to the tank.

I suspect both issues, it's some overstocked old tank syndrome, livebearers from stores often coming pre-loaded with highly infectious and contagious worms, so even if these new fish added last Thursday didn't introduce the disease, the last introduced livebearers could have introduced worms months ago even, they can carry them for a long time while spreading it to every other tankmate, before you start noticing the effects.

The combo of long term high nitrates in an older heavily stocked tank with the bioload increading all the time from the growing batches of livebearers, and new stock added, without quarantine and treating for worms etc has led to a tipping point, and will take some work to recover, but is fixable!

If you can get those photos please, I'd also do a 30% W/C asap, don't add the stress coat, but the others are fine. temperature match the new water to the tank temp before adding it. That will be first step of first aid, then we need to see the fish, and look for any other signs of other diseases, any sign of worms like skinny, lethargic fish, bloating, red bristles protruding from the anus, long stringy white poop etc

 

[Flowerfairy13]

Can you grab some photos of the tank and fish, please? It sounds pretty heavily stocked and nitrates are high, and you've been adding new stock which adds to the bioload, and without QT, which means diseases/worms etc are easily introduced to the tank.

I suspect both issues, it's some overstocked old tank syndrome, livebearers from stores often coming pre-loaded with highly infectious and contagious worms, so even if these new fish added last Thursday didn't introduce the disease, the last introduced livebearers could have introduced worms months ago even, they can carry them for a long time while spreading it to every other tankmate, before you start noticing the effects.

The combo of long term high nitrates in an older heavily stocked tank with the bioload increading all the time from the growing batches of livebearers, and new stock added, without quarantine and treating for worms etc has led to a tipping point, and will take some work to recover, but is fixable!

If you can get those photos please, I'd also do a 30% W/C asap, don't add the stress coat, but the others are fine. temperature match the new water to the tank temp before adding it. That will be first step of first aid, then we need to see the fish, and look for any other signs of other diseases, any sign of worms like skinny, lethargic fish, bloating, red bristles protruding from the anus, long stringy white poop etc

Thank you so much. I will try to get some better photos tomorrow, it can be tricky to capture them.
I have looked closely for any signs of disease but all of the fish seem perfectly healthy!! I definitely haven’t noticed any signs of worms, but should I treat the tank for worms as a precaution?
Also - is more frequent WC the best way to reduce the nitrate level?
Thank you so much again!

 

[Flowerfairy13]

There could be multiple reasons why your guppies have died. Even if the water parameters are okay, there could still be something infectious where those guppies are sensitive to. But in that case, the water should be checked under a microscope. But be also aware that commercial guppies (especially those form Asian fish farms) are prone to disease, worms or even parasites. And even if you would buy those guppies at different stores, they can still come from the same wholesaler.

Thank you for the response. Do you think that it could be something infectious if the guppy fry are doing okay? I would have thought that they are much more sensitive. Although I can't see every fry all of the time, due to the hiding places like moss in my tank

 

[AdoraBelle Dearheart]

It's super late- if you give the tank a hefty dose of the Seachem Prime tonight, read the label to work out the more generous doseage to treat the whole tank for nitrites/nitrates

This will bind ammonia and nitrites for the next 24-48 hours, and give the fish the best chance of surviving as we gradually reduce nitrates through increasing large and frequent water changes.

Then how soon could you do the water change tomorrow? Roughly what percentage of the water do you normally change weekly? That'll let me know how slow we need to go!

 

[Flowerfairy13]

It's super late- if you give the tank a hefty dose of the Seachem Prime tonight, read the label to work out the more generous doseage to treat the whole tank for nitrites/nitrates

This will bind ammonia and nitrites for the next 24-48 hours, and give the fish the best chance of surviving as we gradually reduce nitrates through increasing large and frequent water changes.

Then how soon could you do the water change tomorrow? Roughly what percentage of the water do you normally change weekly? That'll let me know how slow we need to go!

I will dose it now! I can do a water change tomorrow afternoon. I usually do around 25-30% each Sunday..

 

[AdoraBelle Dearheart]

I will dose it now! I can do a water change tomorrow afternoon. I usually do around 25-30% each Sunday..

Yep, first aid and long term stress relief is definitely going to be increasing water changes.

Remember that when you only change 25% of the water, you're leaving 75% of the bad stuff in the tank and refilling it. This usually is fine for a while, and depending on how heavily stocked the tank is, filtration, how many thriving, fast growing live plants it has as well as a few other factors - can be enough.

But a heavily stocked breeding tank with a lot of food being fed and waste being produced, needs much larger amounts changed more often. But it's easy for that to creep up on you as the routine kicks in and you don't notice how much more heavily stocked it is when you see it daily, it's fine for ages, but chemically, those nitrates and other things are creeping higher and higher. The fish manage the stress for a long time, since nitrAtes are less toxic than ammonia or nitrites, but the long term effects on the fish build and build, until it reaches a tipping point for particular fish, or the tank as a whole, and it crashes.


We have to work up to those increasingly large water changes those, since doing too much too fast affects all sorts of chemistry in the tank, and sudden big changes can cause things like swings in pH, that can prove fatal. So it's urgent, but we also have to pace it so as not to put the fish into shock and kill them by doing too much, too fast.

Gonna tag some people that are better at the chemistry thing than I am, so they can help! I'm rubbish with the chemistry, but inherited a tank much like this one when I first got into the hobby, and had to drag it out of old tank syndrome and gradually make changes to fix it and then medicate all the fish, so I'm personally invested into wanting to help you and these fish!

Would you be able to do daily, or even twice daily, water changes if needed?

 

[Flowerfairy13]

Thank you so much! You have been so helpful honestly! Yes, I absolutely could commit to daily or twice daily water changes!

 

[AdoraBelle Dearheart]

Oh, and when doing the water change, rinse the filter media in old tank water just so to remove the worst of the muck, don't run it under the tap or anything. Just needs to be clear enough to allow flow, but they're always gonna be a bit slimy and gross, just don't run it under the tap.

Do you use anything to suck up muck and debris from the bottom of the tank/decor when you W/C?

 

[Flowerfairy13]

Oh, and when doing the water change, rinse the filter media in old tank water just so to remove the worst of the muck, don't run it under the tap or anything. Just needs to be clear enough to allow flow, but they're always gonna be a bit slimy and gross, just don't run it under the tap.

Do you use anything to suck up muck and debris from the bottom of the tank/decor when you W/C?

Thank you! Should I be cleaning the media during every water change?
Also yes - I have a sand vac that I use to suck debris from the bottom and between plants etc

 

[AdoraBelle Dearheart]

Thank you! Should I be cleaning the media during every water change?

Nope, won't be needed during every water change, but especially since we'll be giving the tank a good clean and lots of water changes, makes sense to rinse it out tomorrow so it's starting off clear and full flow, and not contributing more organic waste as it returns and can working at max capacity to process the fish waste.

What filters do you have on there, BTW? I suspect you need more, and the tank is overstocked I'm afraid... but we can manage that for now with stepping up the water changes gradually, then once safe, doing much larger weekly or even biweekly water changes to maintain lower nitrates, and improve things overall!

Then we can look at medicating the fish for both round and flat worms - sorry, but with random fish store fish, especially livebearers, worms are almost guaranteed! But getting the general tank chemistry sorted will boost the fishe's immune systems, reduce their overall stress and reduce losses from nitrate poisoning and possible ammonia spikes.

Also yes - I have a sand vac that I use to suck debris from the bottom and between plants etc

Brilliant - suck up as much waste and debris/remove any rotting organics like dead plant leaves, and as many pest snails as possible, while doing the water change tomorrow. Stick to 30-35% of the total water volume removed, and rinse the filter media. Dose the tank with seachem prime again.

A few hours after the water change and filter clean, test the water again for ammonia/nitrites/nitrates and pH if possible, and let us know the numbers, and how the fish are doing! Watch them for a while and look for any signs of illness or disease.

Oh, crucial not to overfeed, too! Would be ideal to fast them for a few days, and do them no harm at all, but if you really want to, only feed a tiny amount of bug bites, much smaller than you usually would.

Then it'll be daily water changes and testing until they're back in good numbers and while we check out the fish for any other issues, you give us as much info and pics/vids as possible, and then we can worry about if there's anything else going on, then when/whether to medicate for worms. But the worms are less urgent than the water changes and general old tank syndrome, and the improvements in water will help the fish bounce back whatever illnesses they may have, and more able to handle the stress of medication.

Personally I would, and going forward, going to need to reduce stocking and quarantine new stock, but worms are just so likely, even last Thursdays guppies are likely carrying them, so will be best to treat the whole tank, then in future, QT new fish before adding to main tank.


Adding more filtration and fast growing live plants will also help to manage better water quality and give you a bit more breathing room, so you're not so dependent on huge water changes, but will still need to be larger at least weekly water changes to manage the current stocking. It's a big tank, but it's a lot of fish, a few very greedy and messy species, and a lot of them being bred and stocking it even more heavily

Gonna tag @Essjay , @Colin_T @Seisage @gwand and @TwoTankAmin for their chemistry and advice wizardry!

Don't rush out and buy dewormer, BTW, some are rubbish and a waste of money. eSHa NDX and eSHa GDEX are the ones in the UK I know of that contain the right ingredients to treat both round and flatworms, I've used them safely in planted tanks with shrimp, but have to follow the guides for both wormers, and tank and fish aren't yet ready to handle a round of meds. I personally used and recommend that brand though for finally eradicating worms in my own livebearer tanks, while a lot of de-wormers aren't very effective, or can be poisonous to snails and shrimp. I can check my own bottles to remind myself how I staggered treatment another time.

 

[rebe]

fast growing live plants will also help to manage better water quality and give you a bit more breathing room, so you're not so dependent on huge water changes,

@Flowerfairy13 I can give you some cuttings of my fast growing plants, not masses but enough to get started since they are fast growers. I can give you some cuttings of Egeria densa (dense waterweed), Ceratophyllum Demersum (Hornwort), and Limnophila Sessiliflora. The salvinia auriculata is still yours too, and if you'd like them, the new java fern plants that were grown from the leaves of my java ferns.

I don't have experience with worms as fish parasites so @AdoraBelle Dearheart will know better than me, but would some worming medications also wipe out your snails?
Internal worms would be different I'm sure but with other worms like planaria some remedies like 'No Planaria' would wipe out your bladder snails. I don't know about nerite snails.


Edit: I just looked back and saw that Adora already answered the question. Worth checking any de-wormer either of us gets.

 

[Flowerfairy13]

Nope, won't be needed during every water change, but especially since we'll be giving the tank a good clean and lots of water changes, makes sense to rinse it out tomorrow so it's starting off clear and full flow, and not contributing more organic waste as it returns and can working at max capacity to process the fish waste.

What filters do you have on there, BTW? I suspect you need more, and the tank is overstocked I'm afraid... but we can manage that for now with stepping up the water changes gradually, then once safe, doing much larger weekly or even biweekly water changes to maintain lower nitrates, and improve things overall!

Then we can look at medicating the fish for both round and flat worms - sorry, but with random fish store fish, especially livebearers, worms are almost guaranteed! But getting the general tank chemistry sorted will boost the fishe's immune systems, reduce their overall stress and reduce losses from nitrate poisoning and possible ammonia spikes.




Brilliant - suck up as much waste and debris/remove any rotting organics like dead plant leaves, and as many pest snails as possible, while doing the water change tomorrow. Stick to 30-35% of the total water volume removed, and rinse the filter media. Dose the tank with seachem prime again.

A few hours after the water change and filter clean, test the water again for ammonia/nitrites/nitrates and pH if possible, and let us know the numbers, and how the fish are doing! Watch them for a while and look for any signs of illness or disease.

Oh, crucial not to overfeed, too! Would be ideal to fast them for a few days, and do them no harm at all, but if you really want to, only feed a tiny amount of bug bites, much smaller than you usually would.

Then it'll be daily water changes and testing until they're back in good numbers and while we check out the fish for any other issues, you give us as much info and pics/vids as possible, and then we can worry about if there's anything else going on, then when/whether to medicate for worms. But the worms are less urgent than the water changes and general old tank syndrome, and the improvements in water will help the fish bounce back whatever illnesses they may have, and more able to handle the stress of medication.

Personally I would, and going forward, going to need to reduce stocking and quarantine new stock, but worms are just so likely, even last Thursdays guppies are likely carrying them, so will be best to treat the whole tank, then in future, QT new fish before adding to main tank.


Adding more filtration and fast growing live plants will also help to manage better water quality and give you a bit more breathing room, so you're not so dependent on huge water changes, but will still need to be larger at least weekly water changes to manage the current stocking. It's a big tank, but it's a lot of fish, a few very greedy and messy species, and a lot of them being bred and stocking it even more heavily

Gonna tag @Essjay , @Colin_T @Seisage @gwand and @TwoTankAmin for their chemistry and advice wizardry!

Don't rush out and buy dewormer, BTW, some are rubbish and a waste of money. eSHa NDX and eSHa GDEX are the ones in the UK I know of that contain the right ingredients to treat both round and flatworms, I've used them safely in planted tanks with shrimp, but have to follow the guides for both wormers, and tank and fish aren't yet ready to handle a round of meds. I personally used and recommend that brand though for finally eradicating worms in my own livebearer tanks, while a lot of de-wormers aren't very effective, or can be poisonous to snails and shrimp. I can check my own bottles to remind myself how I staggered treatment another time.

Thank you so much! A little update this morning. I was up early to do a water change before the morning rush began here... I tested my well water for Nitrates and got a reading of 10PPM. Then tested my tank water immediately after the change and again got a reading of 10PPM. I will test again this evening to check and if Nitrates have spiked again I will do another water change.
While doing the change I made sure to suck up as much debris as I could and I spent alot of time examining the fish. All of them look healthy and active to me and I don't see any obvious signs of infections.
I am lucky enough to have an amazing friend who lives local to me who has very kindly offered to give me some of her floating plants & cuttings from her fast growing plants to try and reduce the nitrates & keep them under control going forward. She is so knowledgable on almost all aspects of tropical fish & I'm so lucky to have met her!! She is the one who introduced me to this forum.
In relation to stocking - I have found someone who wants to rehome the neons (fully aware of the tank situation and has a QT tank which they will go into before they go into her main tank), so hopefully this helps with the overstocking issues. I truly didn't think the tank was overstocked to be honest, and had actually planned on adding more stock so I am really grateful for your advice!
In relation to the QT tank, yes - my plan for a few months has been to buy a 54 L tank to use as a QT tank but every time I have enough money saved something else seems to come up and the QT tank becomes less of a priority
With my filter - I will pop the link below. I have 2 of these going at the moment and have had for months as I was conscious of the bioload when the fry started to appear. I also have activated carbon with the sponge cartridge in these filters. https://www.amazon.co.uk/gp/product/B0868BTTQ5/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I have also started fasting them for a few days.
Thank you SO SO much again for all the effort you put into helping me, I am truly grateful

 

[Flowerfairy13]

@Flowerfairy13 I can give you some cuttings of my fast growing plants, not masses but enough to get started since they are fast growers. I can give you some cuttings of Egeria densa (dense waterweed), Ceratophyllum Demersum (Hornwort), and Limnophila Sessiliflora. The salvinia auriculata is still yours too, and if you'd like them, the new java fern plants that were grown from the leaves of my java ferns.

I don't have experience with worms as fish parasites so @AdoraBelle Dearheart will know better than me, but would some worming medications also wipe out your snails?
Internal worms would be different I'm sure but with other worms like planaria some remedies like 'No Planaria' would wipe out your bladder snails. I don't know about nerite snails.


Edit: I just looked back and saw that Adora already answered the question. Worth checking any de-wormer either of us gets.

Thank you so much Rebe, you are an angel! I have FB messaged you