Catfish Die off no other fish affected

[nicofish]

It all started a couple of weeks ago. I bought a little royal pleco for my 75 gallon filtered by a fluval FX5. On day 8 his eyes appeared sunken and he died shortly. I returned to the store and got a peckoltia compta by accident sold to me as fake tiger pleco.

That fish died overnight.

I have never had such losses when introducing new fish. This tank has been running for roughly 6 years. The store tested my water my PH was a bit hard (7.8 ), but there were no other apparent problems (ammonia, Nitrate, nitrite were good).

Today. I am going down to feed and I notice one my my older p. maccus died along with a microglanis sp?. At this point I have no idea what is going on. Both of those fish are super hardy and they both appear to be very healthy. They were both darting around for food a couple days ago.

There are 5 silver dollars, a small angelfish, large p. armalatulus (older than the tank) a few guppies and 10 assorted cories.

At this point I have no idea what is going on. there were no sores on either fish, no apparent fungus, no apparent fin issues, etc.

Prior to the purchase of the royal I had introduced a piece of drift wood from a local river. This wood was dried in full sun and scrubbed before being put into the tank. The wood looks like it is silver maple, and it was in the tank for quite a while with no issues. The clown plecos were feasting on it (one clown is still alive and in apparent perfect health).

I suspect either that the wood is contaminated, that the royal brought in some sort of pathogen, or that I am being hit by some bad luck.

If any one has any advice please chime in.
I will be testing my water tomorrow.
I may also dissect the fish to see if there are parasites.

[Bas Pels]

Once I had a problem with all Geophagine fishes dieing and all others not having any problem. Virussus can be rather specific - so if it is something only affecting catfish, it can be a virus.

Virusses are very hard to medicate - firstly you will have to know what it is, than a medicine has to be developed. Pactically speaking, if a virus affects your fishes, you will not be able to do anything

Antibiotics affect bacteria, and a virus is not a bacterium. Therefore antibiotics will not do anything, but they will weaken the fishes, making them more vulnerable for diseases.

[dw1305]

Hi all,
I'm sorry for your losses.

My suspicion would be that it is a low level of dissolved oxygen issue. When the water is warm it can hold less oxygen, and that value is further depressed by low atmospheric pressure. Dissolved oxygen is different from nearly all the other parameters, it only needs to be too low for a very brief period to cause fish death.

I know you had your water tested by your LFS, and that the water parameters they recorded aren't necessarily correct, but what were the values for the nitrogenous compounds?

Also because you have Silver Dollars can I assume that the tank isn't planted? and can you tell us what media is in the filter (do you have floss?)

cheers Darrel

[TwoTankAmin]

This is a problem in our hobby, disease diagnosis is difficult. Understanding everything involved is harder unless one has been educated and and then has practical experience the diagnosis, control of, cures form and potential preventative measures involved. We simply are not fish doctors or disease researchers

In addition to the good information above there are other considerations. For one, different species of fish have natural immunities against different disease. Moreover, for some things, if they do not kill the fish, the result is the fish develops an immunity to the disease for some amount of time. The most common fish ailment this applies to in tanks would be ich. This can explain why some fish die fast and others don't appear to be affected at all with certain diseases.

The point is that knowing what might be at work here is not so simple to deduce. If you had the proper connections and/or could afford to pay for it, a proper lab post mortem could most likely identify what is going on. Unfortunately, we hobbyists cannot afford this sort of thing, only the aquaculture industry seems to do this.

The point is that it could be viral, it could be bacterial, it could low DO especially near the substrate.

However, when established healthy fish begin to die not long after the introduction of unquarantined fish or untreated plants, the first thing I suspect is the problem rode in with these things. One of the issues relating to fish diseases in general is stocking density. In many cases heavy stocking increases the odds of disease occurrence and low density has been shown to reduce it.

One disease that is highly variable in how fast it might kill and how deadly it might be is columnaris. This comes in a variety of strains such that some are highly deadly very fast while others are much milder and have much higher cure and survival rates. The problem is the symptoms for different strains will not be the same. The worst ones will kill the fish before any externally visible symptoms can manifest. The typical saddle back and "mouth fungus" we often see do not appear because the fish is already dead.

Wasting disease is most often a parasite, but columnaris, when it shows as mouth fungus, will eventually prevent a fish from eating.

My first thought here was that you are probably dealing with two issues, not one. I think the wasting you noticed and the following rapid fish deaths are likely due to different causes. I realize this doesn't help much as this means two different treatments/solutions are needed. And if it is viral, that becomes a whole different ballgame. With some diseases the only solution is tho euthanize all the affected fish.

As a last observation on dealing with diseases and medication stress. Yes, meds do stress fish to some extent (depending on the med). When some fish are sick and others may not be and we medicate the tank, the unaffected fish will suffer to some extent from the presence of, what is for them, an unneeded med. When fish are dying and we do not know why, the next best thing we can do is to make our best guess and then treat for that. The problem is this can then cause the other fish to have issues which may or may not be the same as what we tried to treat.

I am sorry I cannot offer something more concrete here. But it may help you take a slightly different view of what might be happening. Most certainly you should answer Darrel's (dw1305) questions. A lot of times the route to discovering the cause involves the process of elimination. Most of us pay no attention to Redox issues (what add or removes oxygen from the water). SeaChem advises users not to overdose Prime and use Excel at the same time as both are reducing agents (they take oxygen out of the water). Different causes can result in low DO levels in a tank.

[apistomaster]

Two Tank, You really nailed it in your Columnaris comments.

[nicofish]

Thankyou gor your comments. I have a huge air pump going into the tank. I doubt it was DO. Additionally nothing had been added to the water which could have caused a redox reaction.

Fortunately I work in a water quality lab so I can have my water analysed quite easily. Unfortunately I have not had time to do so. But if I continue to have problems I may do some extensive testing.

After talking over with my boss (he specializes in aquatic bacteria/protozoans)

He thinks it is most likely a virus as many of you had concluded.

Thanks for the sympathy, sorry for the late reply.

I was pretty upset as these fish had been with me for a number of years and had finally started to come out of their caves to receive food.

I have attached a picture of my tank so you can see to what degree it is planted/aerated.

Thanks for your help! I'll keep you updated

[nicofish]

It appears the mystery is solved. Something went wrong with my bacteria in the FX5 my nitrates shot through the roof. I bought done nitrate pads and in going to load up on ceramic rings.

I had cut down my wc from advice my lfs. I guess since I was doing 50% once a week my system couldn't handle it.

[dw1305]

Hi all,

I have a huge air pump going into the tank. I doubt it was DO. Additionally nothing had been added to the water which could have caused a redox reaction.........

It appears the mystery is solved. Something went wrong with my bacteria in the FX5 my nitrates shot through the roof. I bought done nitrate pads and in going to load up on ceramic rings.

I had cut down my wc from advice my lfs. I guess since I was doing 50% once a week my system couldn't handle it.

Possibly not oxygen then.

Do you know what analytical equipment you have in the lab? Do you have a portable DO meter that you could bring home?

The high levels of nitrate are interesting. Do you think you normally have anaerobic denitrification of the NO3 in the filter (as well as aerobic nitrification of ammonia and nitrite)? or do you think that the death of one of the fish caused an ammonia spike and the nitrate levels were the "smoking gun" of earlier elevated levels of ammonia and nitrite?

cheers Darrel

[Bas Pels]

As Darrel implied, nitrates are not that toxic, nitrites and ammonia are, however.

[nicofish]

I'm aware nitrates are not as toxic but I had levels upwards of 100ppm. Also it is possible I had de-nitrification in the FX5 as the tank was running with no maintenance while I was away at university. I cleaned it recently and it was a mess. I'm not sure what could have caused the spike. I suspect it is cause I threw in a bit too much blackworm which was promptly eaten and must have made its way though the cycle.
Though honestly I didn't think 1.5 oz of live black worm could do that kind of damage.

I do have access to a meter that does temp, DO, PH salinity, and conductivity. I'd prefer not to bring it home or put it in my tank as it is large and need to be submerged. I could throw a sample on ice and run out to the lab.

But as far as I understand all the fish I lost, being in loricariidae
Could eventually have used surface oxygen to some extent. Meaning that if DO was the issue I would have lost other fish first.

For not the losses have stopped I threw in some filter media (deep blue) that is supposed to help with nitrates and gave them a water change.

For now I'll return to my normal water change of once a week at 50%.

If anyone has experience with th e deep blue media please share.

I'll keep an eye on the tank and update if anything else happens.

Thank you all very much,

As always you people are the best.

[dw1305]

Hi all,

I'm not sure what could have caused the spike. I suspect it is cause I threw in a bit too much blackworm which was promptly eaten and must have made its way though the cycle.
Though honestly I didn't think 1.5 oz of live black worm could do that kind of damage.

It might have been the final straw, but I don't think it is the whole answer.

I'm aware nitrates are not as toxic but I had levels upwards of 100ppm. Also it is possible I had de-nitrification in the FX5 as the tank was running with no maintenance while I was away at university. I cleaned it recently and it was a mess. I'm not sure what could have caused the spike.

OK, I think that probably helps a bit.

It sounds likely that the water flow through the filter has slowed to the degree where the majority of the filter media has become anaerobic, and that levels of ammonia have risen. Ammonia is toxic at very low levels and additionally nitrification is an oxygen intensive process (you've gone from NH3 to NO3). Nitrite (NO2) is still toxic, but less toxic than ammonia, and nitrate is relatively non-toxic. Measurement of nitrate is less straight-forward than some other parameters (nitrate salts are soluble, so can't be measured directly by colorimetry), but you should be able to get reasonably accurate values with an Ion Selective Electrode, if you have access to one?

You only need a relatively small volume of biological media to provide enough sites for nitrification to occur, and what limits nitrification usually isn't the availability of ammonia or physical space, but the availability of oxygen.

You can never have too much oxygen in your filter.

I do have access to a meter that does temp, DO, PH salinity, and conductivity. I'd prefer not to bring it home or put it in my tank as it is large and need to be submerged. I could throw a sample on ice and run out to the lab.

We've have similar meters, they measure temperature and conductivity because both of these factors effect DO levels (warm water can hold less oxygen, and warm, salty water less again). Salinity is just a conversion factor based on the conductivity reading (35 ppt salinity ~ 53 milliS conductivity). You really have to measure the dissolved oxygen content in situ, unless you can seal the container and then measure the DO almost immediately afterwards? I use one of the planted fish tanks in the lab. to test the membranes on the DO meters, I know that the water will be fully saturated with oxygen during the photoperiod, and that if the meter takes a long time to stabilise at this value the membrane is damaged.

But as far as I understand all the fish I lost, being in loricariidae. Could eventually have used surface oxygen to some extent. Meaning that if DO was the issue I would have lost other fish first.

Rheophilic Loricariids will gasp air at the surface when they are oxygen stressed, but unfortunately they have lost the ability to extract oxygen from it.

Because they are rheophilic they don't "need" to be able to survive low oxygen levels. There is a cost in fitness to retaining features that aren't of any evolutionary value, which is why animals in caves lose their eyes and pigmentation, although they might be useful in the future. Because Loricariidae and Callichthyidae share a mutual ancestor, and both gulp air, it is likely to be an ancestral trait.

For not the losses have stopped I threw in some filter media (deep blue) that is supposed to help with nitrates and gave them a water change.

I'm not familiar with nitrate reduction sponges, but I know you can get them. I assume they work by ion exchange.

For now I'll return to my normal water change of once a week at 50%.

I think that is all you can do. Hopefully now your filter is less gunged up it should be better at nitrification.

cheers Darrel

[PseudaSmart]

Hi, a couple of comments and suggestions after being in the hobby for a long time.

Your statement that your lfs said you were doing to many WC's? I have never heard that one. Had they ever seen your tank? Just because they sit behind a counter doesn't mean they know what the're talking about.

Everyone on this forum wants to help. Unfortunately most of the suggestions are guesses of potential causes and then recommendations for treatment.

You made good observations which help but water parameters are essential. Titration kits cost less than one of the plecos you bought. You can't go back in time to check water.

If you compare them to your observations bacterial, viral, and fungus are immediately ruled out. When subsequent fish are added to a tank and die in less than 24 hours without visible signs show it's not one of these.

You make no mention of your fresh water supply. City, well, RO, etc. both city and well water chemistry change all the time. When I had city water I had to check the water for chlorine/ chloramine every time I filled the storage tub because several times a year they would mega-dose chlorine to clean the pipes.

So, boiling down your list of clues here are the important ones.
First new fish took 8-9 days to die
Next fish died overnight.
Nitrate levels over 100
Ph 7.8
The following information would have diagnoses easier
Ammonia level
Chlorine test
Water hardness Gh and Kh (ph is not hardness)

So it would appear that your eventual diagnosis was correct, poor water quality that continued to deteriorate. The older fish lasted longer because they were larger and had time to acclimate.

Your filter didn't crash it just couldn't keep up.

Jim

[dw1305]

Hi all,

Your statement that your lfs said you were doing to many WC's? I have never heard that one.

I don't think you can change too much water, although I like regular small volume water changes rather than less regular large ones. I started keeping fish in the 1970's, when "aged water" was meant to have all sorts of magic properties, and changing any tank water was supposedly fraught with danger. I used to kill my fish off with sickening regularity, which I now realize probably related principally to the "aged" nature of the water.

Everyone on this forum wants to help. Unfortunately most of the suggestions are guesses of potential causes and then recommendations for treatment. You made good observations which help but water parameters are essential. Titration kits cost less than one of the plecos you bought. You can't go back in time to check water.

We are trying to help. I'd admit I'm a fairly shoddy fish-keeper, but the other posters on your post really know what they are talking about.

I don't tend to test the tank water very often, partially because it is more difficult get accurate and repeatable results than the manufacturers, and sellers, of test kits would have you believe. If you do want to go down the testing route then semi-quantitative titration based kits are definitely the best ones to use.

I use a different approach, one that is based on risk management and removing single points of failure. I still do stupid things, but hopefully I have systems in place that limit the damage done. There is a more complete discussion in this thread (http://www.planetcatfish.com/forum/view ... =4&t=41038), it is quite long thread.

If you compare them to your observations bacterial, viral, and fungus are immediately ruled out. When subsequent fish are added to a tank and die in less than 24 hours without visible signs show it's not one of these.

I agree, sudden deaths usually relate to a fairly catastrophic losses of water quality, dissolved oxygen is different to most other parameters in that it only needs to be at low levels for a very short time period for deaths to occur.

You make no mention of your fresh water supply. City, well, RO, etc. both city and well water chemistry change all the time. When I had city water I had to check the water for chlorine/ chloramine every time I filled the storage tub because several times a year they would mega-dose chlorine to clean the pipes.

We have had this as a problem in the UK as well, I use rain-water, but others have had this problem (http://www.planetcatfish.com/forum/view ... =5&t=36652).

So it would appear that your eventual diagnosis was correct, poor water quality that continued to deteriorate. The older fish lasted longer because they were larger and had time to acclimate.

Your filter didn't crash it just couldn't keep up.

My guess as well.

cheers Darrel