My Tropical fish are dying - can you help identify a cause?

Neyite

We've a 60l tropical tank, have had it for a couple of years now. We've had occasional casualties over the years here and there but nothing like this.

The stock we had as of two weeks ago was:
6 green neon tetras
1 glass catfish
1 clown loach
1 platy
1 endler guppy
1 guppy

The above had been in our tank between 3 months to well over a year. We went to a new aquarium shop the weekend before last and got 6 new fish - 3 kuhlii loach and three threadfin rainbow (I'm nearly certain that's what they are). Two of the kuhlii died within 48 hrs. Third one died yesterday and was one of 5 casualties in one day. Something is seriously wrong.

As of today, we have:
1 glass catfish
3 threadfin rainbow - 1 looking peaky this morning
1 endler
1 guppy - also looking poorly this morning.

There are no visible infections or parasites on the fish, gills, eyes etc look normal. They look healthy and are swimming away grand then maybe quieter for a day then die.

Aside from our water being slightly hard from the very beginning of fish-keeping, the ph/nitrate/ammonia etc tests have been within range, our temperature within range and water changes done the recommended way and frequency from the start. Ditto with gravel and ornaments - they are in the tank ages, a minimum of a year I'd say. The only thing that I can think of that was different was that our bulb was gone for a couple of weeks, and we had to wait until we tracked down the right size, but I've not seen anything online where that might be a cause for all our losses in such a short space of time.

It goes without saying we wont be restocking until this is fully resolved. I'm assuming that our remaining six fish are hardly likely to survive at this stage, but need to figure out what caused it in order to be vigilant about it in the future, if we can fix it thereby saving the remaining fish, or do we need to go back to the very start and cycle a new tank from scratch after nature takes its course with our last few fishies.

Any suggestions on what we are dealing with?

Sleepy

If there's nothing visible I'd assume some sort of disease. It's almost a certainty that it's something the new fish were carrying when you got them from the shop (would be interested to know where it was, any of the better guys should make amends if they sold you something that wiped out your tank).

I'd do a large water change (50% or so) and treat with eSHa 2000. It's the fish equivalent of penicillin in that it's a broad spectrum treatment for various diseases and, ime, an extremely effective one. You should be able to get it in any decent aquatics / pet store.

If that doesn't work and you lose everthing, I'd be inclined to do a full tear down of the tank and start the cycle from scratch. It's probably over-kill but I'm in the better-safe-than-sorry school of thought. You could try a large (50% or so) water change and leave the tank unstocked for a week or two (with nothing there to carry the infection it should die off quickly enough).

Neyite

Thanks Sleepy, I'll stop off at a pet store for it on my way home, assuming I've any fish left to treat . If they haven't survived the day, can I still medicate the water and save us cycling from scratch again or is that advisable?

Should I talk to the place that sold me the new fish and let them know?

Sorry, just saw your update there about the water changes etc. Think thats the most sensible thing to do.

Alkers

Rather than a 50% water change I would be going with maybe 20% first off and then 10% daily.
Did you quarantine the new fish or put them straight into your tank? Did you transfer the water they came in, into your tank also? If so that would likely be the source imo.
I would be going back to the shop and explaining things.

Neyite

No, we did our usual- put them bagged into the unlit tank, then after a while open the bag so the water or the fish could very likely have carried something.

I will go back to the shop I think. Its a relativity new business, but I got the impression that the owner and his staff have a genuine passion for fish-keeping, and they did know their stuff. They had a tank they were medicating on the day, and it could be that whatever they were treating had spread unknowingly to another tank and they didn't realise until after we had gone off with our purchases.

Would it be cheeky to ask them to help with the cost of restocking? It's about €70 worth of stock.

Sleepy

I'd be surprised if they don't offer at least a hefty discount on re-stocking and if they weren't offering, I'd be asking tbh.

For the future, when adding new fish, if you don't have a quarantine tank (I don't either) net the fish out of the bag so anything in the water doesn't come across into your tank and keep a bottle of eSHa in your cabinet.

fred funk }{

It's nearly always water quality that causes this. What exactly are your water parameter results?

Neyite

fred funk }{ wrote: »

It's nearly always water quality that causes this. What exactly are your water parameter results?

I'm at work so don't know the exact parameters, it was someone else who tested the water and when I asked had said it was the same as usual - no spikes in anything.

But I'll test again when I go home.

EdenStudios

Reading the subject line, I initially I thought this was going to be a case of:
giant-worm

I'd be careful about approaching the original shop. There's simply no proof that it was their contamination. And if their water quality was so bad, how come their fish were alive to purchase in the first place?

Neyite

EdenStudios wrote: »

Reading the subject line, I initially I thought this was going to be a case of:
giant-worm

I'd be careful about approaching the original shop. There's simply no proof that it was their contamination. And if their water quality was so bad, how come their fish were alive to purchase in the first place?

I'd run a mile if that creature was anywhere near my tank! :pac:

I wasn't planning on going in with guns blazing - that's not my style. I'm going to them this evening to get the medication that Sleepy mentioned up thread and while I'm there, chat about the problem and see what they suggest. When we bought the fish, they had a quarantine tank they were medicating that they pointed out to us explaining why those ones were not for sale. For all I know they could have had fish casualties in the days after our purchase just like we did.

I've had a pm discussion and it seems that the shop in question is a pretty reputable one who are very likely to offer some sort of redress if it was likely that the cause was by introducing their fish, so I'm hopeful that they will be helpful.

EdenStudios

Good luck with it. Hope you find the cause.
Used to keep tropical fish about 30 years ago and loved it. I know how seriously the whole water chemistry things is to fishkeepers.

Neyite

So, went into the shop, explained just like I did in my OP. The first thing that they said was a cause was the ammonia. I said that no, the readings were ok, so then they said "bacterial so!" Yer man handed me some Melafix which cost €11, and said it was what they used to dose one of their tanks two weeks ago and it slowed down their losses dramatically.

We had a chat about the origin of the bacteria. He said that it could have been the new fish we bought there, or it could have been an existing bacteria that the oldies were immune to in our tank that wiped out the newbies. I said that this didn't explain the losses of nearly all our oldies. So then he said that our old fish passed a bacteria onto the new guys and they passed it back and they died because of that. Then he said that even if you wash your hands with soapy water, rinse them then stick your hand in the tank, that that is introducing bacteria that can kill your fish. But basically the end of the convo was when I mentioned that we lost €70 worth of stock and that a possible reason was bacteria from the new fish, was [paraphrasing] that all fish carry bacteria, and introducing new fish into your tank means you risk total wipeout every time. That an isolation tank is the only way to be sure. Then he told me that I'd soon get the hang of it - I corrected him on that.

I got the feeling that I was bulsh!tted a bit, and even if they had said "look, we cant say for definite that it came from our fish, and we cant give you free fish /refund you etc but as a goodwill gesture we will give you the medication for free", I'd have been ok with that. Buying the fish was the first time I went into that shop, and I had been impressed with their stock and their knowledge on their fish - I'd even talked to the guy about setting up a marine tank down the line and thought that they might be the best ones to deal with. This visit this evening was my second and last one and I'll get our fish supplies elsewhere from now on. Maybe I'm being unfair though and if I am please tell me!

I'm now home. One of our new Threadfin has disappeared, so likely he's a goner too. And our guppy is still looking dodgy. I took a reading and its as follows:

GH 180 - guide says caution. Its always been a hard-water area, and we tried softeners but they didn't change the reading.
KH 80 - ideal
PH is 7.5, slightly higher than ideal but not within danger range
NO2 is 0 - Ideal
No3 is 80 - caution, but it had been at 40 in the reading the night before all the fish died.

So, I'm going to dose the tank with Melafix, and something for the Nitrate. Then once our tank is safe for fish again, I'll be going back to a previous shop that gave excellent advice and guidance.

Alkers

Where abouts in the country are you located? I only have one shop in the Dublin region that I trust for live stock and no bs!

Neyite

I'm in the west, and there are a few shops to choose from locally luckily - one is a chain, but the guy in the fish part of the pet shop is a qualified marine biologist and very knowledgeable and honest. There is another independent guy, and he's given us good advice on our stocks that cost him sales. There are a few more but one nearly always has a few dead fish in their tanks so not a good sign!

Silverfish

Neyite wrote: »

So, I'm going to dose the tank with Melafix, and something for the Nitrate.

What's the something for the nitrate?

80 is really high, it should never really go above 20 - 40 max before fish have issues.
The only thing that gets rid of nitrates is regular water changes - 25% weekly.

It's possible it was a bacteria, but it's also possible it was an increase in the bioload causing water issues - this can kill off an already fragile fish if it's vastly different from the water it's used to.

Do a large water change to dilute the nitrates, check for ammonia / nitrites / nitrates.

If you're getting more fish, can I recommend more of the ones you have already, as they're all shoaling fish and will be healthier in a group of 6, except for the clown loach, it's a shoaling fish but is meant to grow very large, and your tank is too small for a shoal.

Neyite

Thanks Silverfish, I'll be focusing on shoals again next round, and our clown was one of a pair, and had an idea they grew big, possibly too big for a tank, but we were told in the shop that they were perfect for tanks.

OH did 2 big water changes last night and a few days ago too of about 30% each time so the 80 is a real concern right now.

I've just noticed that our test strips don't test for ammonia. I'll do that now with a test tube one: We also tested the nitrate again and the nitrite: Now this is where its getting confusing - The dip strips are telling us the Nitrate is 80 for the second time this evening, yet the test tube test are showing this,which seems to indicate that they are not bad at all:

Silverfish

Do not use the dip strips, trust the tubes!

Did you give the nitrate test bottle a really hard shake? Sometimes it can give a false good report when it's become separated in the bottle.

I usually give it a few thumps on a table as well, actually

Neyite

I did. Gave it a big shake there, and a couple of thumps - Still a shade or two darker than the lightest yellow but nowhere near the pale orange shade of the 0.5.

So I can take it that the Nitrates are grand so? Phew. So the only things are a slightly higher ph, but its been a consistent 7.6 on all our historical records. The hard water is something that the dipsticks are saying is high so maybe I'll pick up a tubes kit for water hardness and see if that gives a less alarming reading.

Silverfish

Neyite wrote: »

I did. Gave it a big shake there, and a couple of thumps - Still a shade or two darker than the lightest yellow but nowhere near the pale orange shade of the 0.5.

So I can take it that the Nitrates are grand so? Phew. So the only things are a slightly higher ph, but its been a consistent 7.6 on all our historical records. The hard water is something that the dipsticks are saying is high so maybe I'll pick up a tubes kit for water hardness and see if that gives a less alarming reading.

It's best to test kH/gH - its easier to match the fish to the water you have than try match the water to the fish!

Neyite

Thats a very good point. Fish that do well in hard water from now on so.

fred funk }{

A sudden Ph change is deadly to fish which can happen if there's low kh present. I would also test your tap water.

Neyite

fred funk }{ wrote: »

A sudden Ph change is deadly to fish which can happen if there's low kh present. I would also test your tap water.

Its always been around 7.5 /7.6, but I will test it with the tubes and test the tap water too.

Sleepy

I'm surprised to see <snip> recommending Melafix tbh. The eSHa 2000 I recommended above would be a far better wide spectrum anti-bacterial treatment...

A ph reading of 7.5 wouldn't concern me unless I knew the fish needed a very specific PH range and, as it's been the same throughout, was hardly the problem for your fish.

The increase in bio-load causing a spike in Ammonia and a mini-cycle could be a possibility but you're fairly on-top of things with water changes and the test kits aren't indicating that this is happening (you wouldn't be getting a 0 for Nitrite if this was the case).

TBH, I think whoever you're dealing with is bull****ting you, the fish you got from them introduced some infection to your tank imo. I know a lot of aquatics stores run treatments like eSHa 2000 permanently as with ever-changing stock, there's almost always some sort of infection coming into the store and few have the time or margins to enable them to properly quarantine new stock.

Neyite

I think they suggested it because they didn't stock the eSHa2000. But I didnt want to leave empty handed and not medicate the tank for another 24hrs

I'll stop off at a different pet shop this evening and get the eSHa2000. It's probably good practice to have it at home to hand.

The poorly ones from yesterday are gone now too - the guppy and one of the threadfin. We now have a single endler, our glass catfish, and two threadfins left. I suggested to OH that we do our research and build a good community of fish that are hardy enough for the slightly higher PH and GH. It might be that we'll need to choose breeds that are not compatible with our few remaining fish but we could rehome those I'm sure if it came to it.

fred funk }{

Neyite wrote: »

Thanks Silverfish, I'll be focusing on shoals again next round, and our clown was one of a pair, and had an idea they grew big, possibly too big for a tank, but we were told in the shop that they were perfect for tanks.

OH did 2 big water changes last night and a few days ago too of about 30% each time so the 80 is a real concern right now.

I've just noticed that our test strips don't test for ammonia. I'll do that now with a test tube one: We also tested the nitrate again and the nitrite: Now this is where its getting confusing - The dip strips are telling us the Nitrate is 80 for the second time this evening, yet the test tube test are showing this,which seems to indicate that they are not bad at all:

Just noticed the above now. Is that showing high Ammonia or am I reading it wrong?

Neyite

No,
Nitrate is the top tube
Nitrite is the middle one
Ammonia is the bottom one.

Knine

Sleepy wrote: »

I'm surprised to see <snip> recommending Melafix tbh. The eSHa 2000 I recommended above would be a far better wide spectrum anti-bacterial treatment...

A ph reading of 7.5 wouldn't concern me unless I knew the fish needed a very specific PH range and, as it's been the same throughout, was hardly the problem for your fish.

The increase in bio-load causing a spike in Ammonia and a mini-cycle could be a possibility but you're fairly on-top of things with water changes and the test kits aren't indicating that this is happening (you wouldn't be getting a 0 for Nitrite if this was the case).

TBH, I think whoever you're dealing with is bull****ting you, the fish you got from them introduced some infection to your tank imo. I know a lot of aquatics stores run treatments like eSHa 2000 permanently as with ever-changing stock, there's almost always some sort of infection coming into the store and few have the time or margins to enable them to properly quarantine new stock.

Sleepy where would I purchase the esha 2000 please. Sounds like a handy treatment to keep just in case.

Sleepy

Most good aquatics shops will have it. I know they have it in Newlands Garden Centre, Kinsealy Pet Shop used to stock it but I haven't been there in months.