Sick Oscar... beaten?      2/22/13 Had an ammonia spike which lead to lost of slime coat & cloudy eyes. Eyes have cleared up almost all the way. The first day and a half he laid on one-side. Now he is upright but remains on bottom of tank. Have been doing water changes, the salt trick and also added prime to tank water. When I looked at him the other day it appears his flesh popped through his skin. Is there any treatment for this or should I euthanize (if so how) <Something has beaten this fish... What else is in the tank? What re the system itself, size, mechanicals, water test parameters... READ on WWM re what we're looking for information wise... then write back. Bob Fenner>

Oscars Dropping dead! - 12/18/2012
Howdy!
<Hello!>
I hope this gets to the right desk,
<It's on my desk tonight - Sabrina with you this chilly evening.>
and hope this letter finds all in great standings or better.
<Thanks.>
I am floored with the events of the last few days. My boyfriend and myself have an aquarium that we set up earlier last summer. We got 4 young Oscars (two albino, two regular tigers) and put them into the 50gallon tank -
<This is too small by far to house four adult Oscars.  Young Oscars grow up, not slowly either, and are very "messy" fish - i.e., consume a lot of food and produce a lot of waste, thereby fouling the water quality impressively.  I would not house more than one adult in a 50 gallon tank, and even that might eventually be just too much work for my lazy self to keep up with the waste production.>
They where about 3 inches each. Today the remaining two are a good 6-7 inches,
<This is about the largest I would be inclined to keep in a 50g; if it is possible for you to consider a larger tank, please do so.  Otherwise, be prepared to consider more/stronger filtration and more frequent water changes.  Weekly wouldn't be overkill.>
but two have recently died.
<How unfortunate; my sympathies.  Hopefully we can help you turn things around for the remaining two....>
I know your going to want to know the water stuff,
<Yes>
however, I don't have a kit yet (I know, bad fish owner),
<You said it, not me.  Get test kits as soon as you reasonably can for Ammonia, Nitrite, Nitrate, and pH.  These are not just "nice to have", but "urgent".  Since we can't physically see or sense (beyond making guesses based upon scent, color, clarity, etc., which is entirely unreliable and inaccurate) these properties of the water, the only way we can really know what is the status of the environment is by using a reliable test kit. 
These measures aren't just for having fun playing with science at home (even though it is fun anyway), they're crucially important because the water is what the fish are living in full time.  They're not moving around in the air, like you and me, or mice, or cats, or dogs, they're immersed full time in a medium in which you and I don't live.  Control that environment, and you control the health of the animals.>
but these guys have been thriving so nicely in this tank until now!
<The exceedingly precarious balance of too much fish in too small a space finally tipped.  It was inevitable, without constant checking of water quality and large frequent water changes.  Get those test kits....  and change water.  A lot of water.  Like, yesterday.>
Night before last we looked in the tank and noticed that one of the tiger Oscar's scales had seemed to liquefy, some where still hanging on but they where not hard scales - I am having trouble explaining what they look like, but liquefied is my best description - And where hanging off waving in the water like tirn flesh with no hardness or shape like a scale should have.
The flesh between the fins just sort of evaporated on the pectoral fins.
Death came very quick after that.
<Your descriptions are very clear, and almost certainly symptoms of poor water quality.  Perhaps very, very poor water quality.>
We have 2 left, scared to death they will die of this disease.
<They will, if you do not correct this environment as soon as possible. 
Minutes matter right now.  If you can do a water change the moment you get this email, do so.  If you can properly match for temperature and pH and use a good quality Chloramine remover (Jungle brand ACE, Seachem's Prime, or really any other commercially available product that removes Chlorine and neutralizes Chloramine), then I would seriously consider changing 50% of the water or more.  Even if you can't match for pH (since you lack a kit), I would probably still do it.>
We use distilled water because the local water has TONS of chlorine and other chemicals (you can smell it in the water).
<Yikes!  Do not use distilled water!  There is no buffering capacity in distilled water at all, and as soon as waste and dissolved organic "stuff" builds up, carbonic acid builds too, and the distilled water with no buffering capacity drops in pH rapidly - a "pH crash".  This alone can kill fish, very very rapidly, and also with the symptoms you describe.  You would be better off to do a major water change - right now if possible - with tap water treated with the Chloramine remover mentioned above.  If this is what has happened (and I would bet a fair amount of money on it), then you're not going to be able to match for pH, and frankly, what the fish are going through right now is probably worse than the shock of bringing the pH back up with a large water change.  To be safe, perhaps you could try a 25% water change, see how they fare for a couple of hours, and then do another, perhaps larger, water change.>
Is there any hints or tips you could pass along to save the remaining Oscars?
<As above.  And act quickly.  Even minutes are important right now.>
Or have you heard of this before?
<Oh yes.  And seen it.  Environmental disease - reaction, sudden or otherwise, to adverse water quality or other problem(s) in the environment - is probably the "number one" killer in pet fish.  And what makes this most unfortunate is that, once we're all properly educated about it, how easy it is to simply test water, observe water quality, and maintain with simple water changes....>
Thank you for your time
-Sara
<And thank you for your interest in fixing this problem.  I do hope you are able to do so in time.  My best wishes to you and your remaining Oscars, 
-Sabrina>
Oscars Dropping dead! - II - 12/19/2012
You responded so quickly I truly do appreciate it!
<Glad to be of service, Sara!>
I have ordered a test kit that covers all the things listed as of last night.
<Great.>
The other 2 Oscars appear as frisky as ever right now.
<Then let's keep our fingers crossed that we're not too late.>
I am going to do the water changes as suggested getting rid of the distilled, but is it safe to use tap water, conditioned of course?
<Conditioned, yes.  It is possible, of course, that you're in an area with water that's just too "bad", but most places in the U.S. (assuming that's where you are) are "okay" enough to say so.  Oscars are very, very tolerant of a very wide range of pH and hardness, and as long as the water is treated for chlorine and chloramine, chances are it'll be okay.>
Or should I use that filtered/artesian stuff?
<You could use filtered water, spring water, etc., just NOT distilled water.  And be aware that some/many "filtered" waters may need some additional buffering capacity added - something like Kent's "R/O Right" product, or other similar options.  You can also use half tapwater and half filtered/R/O water, which will give you perhaps the best results.  Oh, and as far as "spring" water is concerned....  One of the best road trips I ever had took me through the Owens valley in California, and south toward the Mojave desert.  Somewhere in that saltpan-riddled territory was the headquarters and bottling facilities of one of the major spring water producers.  They're just starting with what I'd call some of the worst water in the nation, and filtering it to what I'd call passably drinkable. 
Filtering your tapwater or purchasing water cheaply at a water filtering facility in your general area (or even from one of those dispenser-type machines outside of supermarkets) is as good.>
I will have my guy go out and get whatever needed for it to be started soon as we know what to do over it. I do have to let you know we are very rural, so zipping out to buy something fish-specific isn't exactly easy (closest Petco is oh, 126 miles off down a snowy highway).
<Ah, I do sincerely understand.  I used to live in Bonner's Ferry, ID, nearest Petco was that far I'm sure - though there was a little mom'n'pop spot outside of Sandpoint, ID, and they got all my business.  Good folks, and only maybe 40 miles away.  I do miss living up there.>
We don't want to lose these fish (I am particularly fond of the last living albino we call "runt" - almost solid white still, no orange, but his fin tips and edges are black). Again, thank you for the quick response!
<My very best wishes to you and your Oscars, Sara.>
-Sara
<-Sabrina> 
Oscars Dropping dead! - III - 12/21/2012
Howdy my new bestest Oscar buddy (Lol, don't worry, not some freak, just always appreciate help)...
<No worries.  I'm freaky enough for the both of us anyway!>
I started conditioning a good bit of water last night (tap water) so it has plenty of time to be just right.
<It should (hopefully) not require much time....  That said, water districts are not created equally.  My own tapwater has a pH in the summer of 9.5-ish, but after neutralizing Chloramine and aerating overnight, the pH plummets to around 6.0!  I'm sure you begin to understand how important those test kits are.  I'm glad they're on their way.>
We plan on doing the change out slow, about 10 gallons at a time with what I have for safely holding water.
<Do be observing those animals closely.  I fear that you're up against time, and moving too slowly might not be in the interest of their health....  You'll just have to find a balance between moving quickly enough to reverse whatever problems are in their environment (Ammonia, Nitrite, perhaps a drastically low pH, maybe other completely different factors) and watching to see if they are adversely affected by the crappy tapwater.>
Yes, I am in a rural area where water is just "off." it IS drinkable, but the chemical content is high here because of our supply's issue with what we call "shrimp." Bugs basically.
<That's.... neat.  Creepy.>
I looked up different colors, I think "Runt" is one of those lutinos?  I found 2 tiny orange spots by his/her tail, but other then that the only colors are the black on the fins (which goes to clear further out on the dorsal fin, with a bit of orange growing along the edge). Rainbow fins!
<Sounds pretty!  Lutino Oscars typically have normal eye color (as opposed to the blazing red of an Albino Oscar's eyes), but can sport even vivid red coloration like the Albinos often have.  The black edge to the fins is not uncommon in Lutino Oscars, as well.>
Thanks! And I'll let you know what happens!
-Sara
<Sounds good.  Take care,  -Sabrina>

Sick tiger Oscar - 8/23/12
Hi,
<Hi Lane, Rick here>
I have asked you questions before about my platys and your advice worked wonders, so maybe you can help me with this. My family just bought a 5 inch tiger Oscar from the pet store and we have had him for about a month. He has never had a problem before and is always active and hungry.  However, for the past 5 days he has not eaten and has been acting very lethargic. He is swimming at the very top of the tank and barely moving.
<Hmm. What's the water temperature? Even though Oscars like the water warm, they still need dissolved oxygen. Do you have sufficient surface agitation?>
I have pellets and feeder fish in there for him and I have tried to feed him on multiple occasions but he just goes to hide.
<Feeder fish aren't the best idea unless you are breeding them yourself.
Can easily import pathogens or parasites. Even then, feeders should be used sparingly. Better to feed pellets and a variety of frozen foods. Oscars aren't very picky eaters.>
On Sunday we performed a large water change of about 60% because the water had become dirty with brown algae which we determined to be new tank syndrome.
<Algae might be a symptom of overfeeding.  Also, watch the relative temperatures of the tank water and the replacement water during water changes.  Thermal shock can produce symptoms as long as days after the water change.>
Our hardness in the tank is a little high but other than that the levels are fine
<quantify? You blamed algae new tank syndrome but other levels are fine. If you have no ammonia, nitrite or nitrate, that seems to contradict your conclusion.>
, even though the tank is continuously filling up with brown algae. How can I clean the tank and heal my Oscar?
<Difficult to make conclusions without the actual data from your water tests. Does the fish exhibit any physical symptoms or only behavioral symptoms?  Any pitting of the head area indicating possible Hole-in-the-head disease??>
Oh and we had another Oscar, but she just wasn't eating since we got her and died about a couple weeks after we got her.
<Could be any number of reasons.>
The tank is 75 gallons and minus the 2 rosy red minnows swimming around that he hasn't eaten he is the only fish. I can't figure out what is wrong with him and I need a solution fast!
<75 is sufficient size for a single Oscar. You'd need over 100 gallons for a pair.  Keep in mind these are extremely messy fish. Watch him eat, you will see food coming out through the gills as the fish tries to swallow. 
Oscars require larger and more frequent water changes than most fish.>
-Lane Vaughn
Re: Sick tiger Oscar - 8/23/12
The temperature ranges from 26.9 to 27.2 degrees Celsius.
<In range.>
His behavior used to be slightly aggressive and he was a total pig, jumping out of the water for food, always coming up to the  tank to eat, etc. Now all he does is sit at the top and barely move.
<Original behavior typical. What puzzles me is that the fish stays near the surface rather than on the bottom. That might point to some sort of poisoning, nitrite perhaps since your value is not zero? Are the minnows behaving abnormally, too?>
And this is only the second time I have given him feeder fish, but he loved them the first time.
<Always risky.>
 He gets plenty of pellet food everyday (not too much, we don't overfeed) and he usually eats all of it the second it gets in the tank, but he hasn't touched it lately. 
<Be sure to remove uneaten food.>
The actual test results were:
Nitrate-0
Nitrite- .5
Total hardness- 75
Total alkalinity- 40
pH- 6.8
<Nitrite should be zero. The tank may still be completing its cycle.. Here in Phoenix, people keep Oscars in water much harder than yours, so I doubt that is your root cause. A few questions then: Has the pH been changing or is it stable? Is the pH of the water put into the tank significantly different from 6.8? Are there any other physical changes or clues you can
observe on the fish, such as a change in the color and/or texture, gasping at the surface, abnormally fast gill movement?  So far the clues still point to nitrite poisoning or possibly insufficient dissolved oxygen, but there is always a chance that some stress activated a latent illness or the feeders brought something in. - Rick>
Re: Sick tiger Oscar - 8/23/12
And also the water temperature of the new water is fine (27) and he has no indications of hole in the head.
<Good. In-line with the other values - Rick.>
Re: Sick tiger Oscar - 8/23/12
<Hi Lane>
Okay so I just did another water test and the levels are the same except the nitrite levels are 0 and the pH is a little bit acidic. Between 6.2 and 6.8, leaning more toward 6.8. I will do another test tomorrow to see if anything changes, but what should I do if the pH isn't stable?
<Consolidating the two emails>
I also just did another sink water test and the levels are the same as they are in the tank except the sink water is a little less acidic than the tank water. Not completely neutral, but definitely less acidic
<6.2 and 6.8 are very different pH values when you consider this is a logarithmic scale, so each integer value is a factor of 10.  If you are using test strips, I recommend a liquid kit as more accurate. My kit has three color-values indicated between 6.2 and 6.8.  Stable pH is very important for any fish. Fluctuating pH can cause serious problems, especially if changes occur quickly.  Soft water is notorious for causing pH drift in the acidic direction, which is consistent with what you appear to be experiencing.  The solution to stable pH with soft water is to use a buffer. Unfortunately, I have the opposite situation with extremely hard water, so I don't really have a lot of experience with buffering tanks and can't advise on the what and how much question. However, here are several sections of the WetWebMedia website with a wealth of information on pH and water chemistry.
http://www.wetwebmedia.com/FWSubWebIndex/fwh2oquality.htm
http://www.wetwebmedia.com/fwsubwebindex/fwph,alk.htm
You might also check in with a reliable local fish store to ask them what they advise their customers to use. It should be relatively consistent locally. But, if it turns out the total alkalinity already in your tank is sufficient, then pH is a red herring and we need to look elsewhere. -
Rick>
Re: Sick tiger Oscar - 8/23/12
I'm sorry to keep bugging you about this but I have been looking up symptoms for pH shock and they seem to be similar to how he is acting but the sites I looked at all had varying symptoms so I was wondering if you would tell me the symptoms of pH shock and how to cure it
<No problem. We've all experienced trying to save animals. You probably get multiple symptoms in your searches because different animals behave and react in different ways, some more sensitive than others. You haven't mentioned if there are any symptoms aside from the lethargy. Anyway, the key here is to get that pH stable to minimize the chances of any latent illness exacerbating the problem.  I still have a sense there might be something else going on, but getting the pH stable will be a good start.
By the way, a quick look-up in one of my books suggests maintaining a buffer of 4 degrees carbonate hardness. -Rick>
Re: Sick tiger Oscar - 8/23/12
Okay so I did another pH strip test and it came out the same. I'm going to get some liquid test strips today
<Good. You can be much more confident in your results. API makes a very good freshwater test kit. They cost a bit more but will last you a long time.>
, but I finally got a good look at him, he was laying on the ground which isn't unusual behavior for him in the early morning,
<Oscars can be lazy at times.>
 and I was able to confirm what I thought I had been seeing. His eyes are cloudy. I don't know what this means or if this will help with the diagnosis. Later today I'm going to the pet store where I bought him to see if they can tell me anything, but other than that the only numbers that are off is the pH is a little bit acidic and the water has a low alkalinity
<That symptom helps. Many of the causes I've seen listed for cloudy eyes, such as cataracts in a young fish, or rare eye flukes, are unlikely in this situation. I didn't find much related to this in a quick WWM search, and most of what I did find was related to marine fish. However, I did find an article on FishChannel.com reinforcing that cloudy eyes can be associated
with low pH. You should read it.
http://www.fishchannel.com/fish-health/freshwater-conditions/fish-cloudy-eyes.aspx
I think this reinforces our pH hypothesis. - Rick>
Re: Sick tiger Oscar - 8/24/12
I went and got liquid test strips <<?>> today, and they gave me the same results.
However, the man I talked to at the fish store said he could have picked up a fungus from the fish that died. That wouldn't surprise me because it started up after she died and she was in there for three days because she died in an ornament and we couldn't find her.
<I see.>
I did a little research and it seems correct, so I have started treating him with Pimafix to cure it.
<I had a feeling something more than just pH shock was going on. I recall that Bob Fenner isn't excited about the herbal treatments. I'm a bit less skeptical about naturopathic methods, but be ready to switch to something more potent if it doesn't work. I'd still track the pH regularly before and after water changes until you understand how it behaves for you.  Good luck and let us know how it goes. - Rick>
Re: Sick tiger Oscar - 8/24/12  9/1/12
He definitely had a fungal infection. He has been getting back to his normal behavior and he is eating more each day. Thank you so much for all of your help!!!! I am very grateful for everything!
<That is terrific news!
- Rick>

my baby Oscar swimming crazy       8/19/12
My Oscar is swimming funny. I have a 55 gallon tank. I have a Jack Dempsey and a small Oscar, well the Jack Dempsey beat the little Guy up, by eating tail and side fins.
<Completely predictable. Don't keep them in the same aquarium. Since Oscars need a 75-gallon aquarium, minimum, you may as well buy the new tank. Did you do any research? Didn't you read about how Oscars are large, territorial towards their own kind, but basically peaceful? That Oscars prefer soft, slightly acidic water? Compare this to Jack Dempseys, which are hostile, bad-tempered fish that need hard, alkaline water. No-one who's done research would keep them together. They're fundamentally incompatible fish.>
I put the Oscar in a smaller 10 gallon hospital tank he was doing fine but now he gets stuck to the side of the filter and swims in circles and flips.
<Doesn't have any fins, so swimming isn't easy. Plus, 10 gallons is insanely small for even a baby Oscar. Hospital tank needs to be at least 20 gallons for this species. What's water quality like? How did you mature the filter in this aquarium before adding the fish? Any nitrite or ammonia in the water in this tank will make a bad situation even worse.>
I got him Melafix
<Waste of time, money.>
gave him fresh peas and little chunks of earth worms, but he won't eat.
<If cichlids don't want foods, it means they are very, very stressed and sick. Medicate as per Finrot using a good quality medication (Maracyn 1 and 2, used together, works well).>
Please help I feel sorry for the little Guy.
<I bet. Do read above, then here:
http://www.wetwebmedia.com/fwsubwebindex/oscars.htm
Follow the links to do with health and systems. Your problems here are entirely of your own making; that means they're easily fixed if you change
how you keep your pet fish.>
Thanks much Cassie
<Most welcome, Neale.>

Oscar fish... distressed in uncycled system 1/11/12
My fish is going crazy when i get close to the tank. He haven't eaten in 8 days. The levels or fine we put him in a 55 gal 8 days ago.
<... this system isn't cycled. The chemistry here is the likely cause of this fish's troubles, troubled behavior>
He cut himself going crazy on side of face. I don't know what to do please help me.
Thank you.
<Read here: http://www.wetwebmedia.com/FWSubWebIndex/fwbiofltfaqs.htm
and the linked files above. Bob Fenner>
Re: Oscar resurrection! 1/21/12
Hey thanks for the help my Oscar is back to healthy in fact i hadn't seen it so active in a while :-)
<Glad you had such success! Cheers, Neale.>

Astronotus; diet, health 1/8/12
Hey there I'm new to this but I have an Oscar almost 3 years old
<You're new to fishkeeping and only just got this 3-year-old Oscar? Or you've kept this Oscar for 3 years but feel like you're a new fishkeeper?>
he has been swimming upside down for two days I've read that a lot of goldfish is bad
<Yes. Why are you feeding your Oscar goldfish? That's the single best way to ensure your Oscar gets diseased. There are no books on Oscars that recommend goldfish, and no experienced fishkeepers writing in magazines or websites. So I have to ask, where did you get the idea to use goldfish from? Sometimes people keep predatory fish because they want to see one fish kill and eat another fish. You can find videos on YouTube of teenage boys (with social inadequacies, I have to assume) videoing this sort of thing, usually with rock music in the background. Depresses the heck out of me. Please don't follow their lead. Oscars need a mixed diet, largely based on good quality pellets such as Hikari Cichlid Gold, with some fresh or frozen foods such as tilapia fillet, cockles, prawns and mussels used now and again. If your fish can't balance itself, it may be constipated, in which case Epsom salt together with a diet of JUST cooked peas will help (no, he won't eat the peas at once, but when hungry, after a few days, he will).
http://www.wetwebmedia.com/fwsubwebindex/SaltUseFWArtNeale.htm
http://www.wetwebmedia.com/fwsubwebindex/gldfshmalnut.htm
But if the problem is more serious, as it could easily be, then we'll need more information on this Oscar's world. How big is the tank? What is the water quality like? How often do you do water changes? Apart from goldfish, what food do you use and how often?>
so I think that might be the problem he also has a bump coming out his left
<His left'¦? Cheers, Neale.>
Re Astronotus; diet, health 1/8/12
The tank is 48g I change the water ones a week he shares it with 3 jack Dempsey I've had him for 3 years
<Too small, as I'm sure you realise. Oscars alone need at least 75 gallons (though often mentioned, 55 gallon tanks quickly become filthy and nitrate levels are very difficult to control in tanks that small). Add a bunch more cichlids like the ones you have, and you need a tank 100 gallons or larger.
How much water do you change? I hope at least 25%. How big is the filter? I hope at least offering a turnover rate not less than 8 times the volume of the tank, i.e., 48 x 8 = 384 gallons/hour. Nitrate levels must be 20 mg/l or less; ammonia and nitrite must be 0. This fish is almost certainly being stressed, harmed, killed by the environment you've provided. Without improving his world, medication won't be much/any use. Nitrate poisoning, constipation, Thiaminase, Hexamita, secondary bacterial infections -- all
these are possible explanations for the symptoms you're observing. Cheers, Neale.>
Re Astronotus; diet, health
Water temperature is 80 degrees I usually feed him Hikari pellets water change is 25% weekly
<Given how small your tank is, I expect you will need to do more water changes than this to keep nitrate levels low enough. In any event, the rest of my comments stand. This fish has been stressed by the environment you've provided. Read through my messages and act accordingly. Cheers, Neale.>
Re Astronotus; diet, health 1/8/12
Thank you very much
<Glad to help. Neale.>

Astronotus; health 12/22/11
Hi, I have two Oscars and my smaller 3 inch Oscar is turning pale. They are both black, but the smaller one is turning a pale olive green at the top of his/her body... Is this normal, what can I do, I'm extremely worried about my fishes life!
<Need some information here, Nicky. How big is the aquarium? Have you measured water quality recently? Let's recap. Oscars need big tanks and extremely heavy-duty filtration. For two specimens you'd need at least 75 gallons, even for babies, and the filter should provide a turnover rate of at least 8 and preferably 10 times the volume of the tank per hour. For two Oscars, I'd be using two Eheim 2217 canister filters or similar. Almost all problems with Oscar health come down to poor environmental conditions -- not enough aquarium space, not enough filtration. Cheers, Neale.>
<<Neale, WWM referral? B>>
Re: Astronotus; health 12/25/11
I noticed my temperature was off and that made him go back to normal color... but now the big one keeps swimming on his side. basically these to fish belonged to my friend who could no longer care for them. He housed them in a ten gallon tank and passed them to me. I can't afford a bigger tank at this moment, and the Oscars are very small.
<Hello again Nicky. There's really not much else I can say here. I appreciate you're doing your best to help these fish, and that you're stuck with the aquarium you have for the short term. But Oscars aren't "social" fish and won't get along without plenty of space. Males are aggressive towards one another *and* towards unreceptive females, and mouth-to-mouth and mouth-to-flank interactions are common examples of aggression. In terms of water quality, you need to keep nitrite and ammonia at zero, and nitrate below 20 mg/l, so heavy filtration and likely water changes more than once a week will both be part of the maintenance regime. Do read:
http://www.wetwebmedia.com/fwsubwebindex/oscars.htm
Cheers, Neale.>
Re: Astronotus; health, and comp. f' 1/5/12
Okay one last question it's, my big Oscar has almost killed my smaller Oscar. My smaller Oscar's scales are ripped all the way off. Leaving white dermis. He can't eat anymore because he can't swim to catch food. His fins have been ripped between the connective areas. He is on his side and can only breath. So i put him in a fish carrier. There is a heater as well in there. He has been in there for the past week and a half. My main question is, is there a way to supplement his diet, since he can't eat. Vitamin drops???! I put Melafix for the fins.
<Melafix is not helping here; you need a proper antibiotic or antibacterial, e.g., eSHa 2000 or Maracyn. Vitamins are irrelevant. This fish needs a hospital tank (at least 30 gallons for an Oscar) with a heater
and filter where it can recover for a few weeks. Long term, each Oscar needs at least 55 gallons, preferably 75 gallons. As I've said before, Oscars are not social and yes, the bigger one will want to kill the smaller one. Putting the fish in a "fish carrier" (whatever that is) won't help. If you can't do any of what's required, euthanasia may be the only option.
Possibly, a pet store could take one or both fish from you, or you could make an appeal on a fish club forum or at a city aquarium club. Cheers, Neale.>

Red Oscar wont eat medicine 11/20/11
Dear WWM,
<Hello to you both.>
We have a 2 year old red Oscar and a 1.5 year old tiger Oscar with a Pleco in the same 55g tank.
<Your tank is much too small for all these fish together. It's barely adequate for even one of them kept alone. Consider 75 gallons the absolute minimum for two Oscars together, and 100 gallons the minimum if you want the catfish too.>
About 2-3 months ago the red male Oscar developed hole in the head,
<Almost certainly down to the size of the tank. The thing with cichlids is that they're acutely sensitive to non-zero nitrate levels, and in small tanks, it's difficult to keep nitrate below a safe value of 20 mg/l. The bigger the tank, the more water to dilute the nitrate, so the better the health of the fish. Other factors very likely come into play, including fresh greens in the diet (wild Oscars consume fresh greens as the gut contents of their prey as well as consuming some plant material directly, and in aquaria it's critical to respect that). Low oxygen concentration in an overstocked tank is a third factor likely behind HITH disease.>
and we tried the general cure from Pet-Smart... it did nothing.
<Indeed not.>
He was eating well up until about 7 days ago. We have been trying to feed him this medicated fish food from Jungle, that worked the last time he had hole in the head (which cured him last time), but this time he just won't eat it. He won't eat much, actually'¦ He seems severely lethargic and only has come out to swim (from his house) once in a great while, or when attacked by the other Oscar. We tried the Melafix with aloe,
<Useless.>
and that seemed to perk him up a little, but did nothing else. We tested the tank water, and the ammonia is fine; but the nitrates are not good.
<See above. Cichlids must have nitrate levels below 20 mg/l, and ideally as close to 0 as possible. Can't do that? Don't keep cichlids. I've seen cichlids develop HITH time and time again in overstocked tanks, and almost every time I see cichlids with HITH, it's the same problem: overstocking, lack of water changes, high nitrates, monotonous diet. Throw the use of feeder fish into the mix, and things become even worse.>
The water is soft, the ph, nitrites and everything else is fine on the test.... What do we do?
<Buy a bigger aquarium.>
Is there any chance we can save our Red Oscar?
<Yes; treatment requires Metronidazole, also known as Flagyl, as directed by the manufacturer or your vet. Success rate is pretty good if treated promptly:
http://www.wetwebmedia.com/flagylfaqs.htm
Naturally, environmental conditions need to be fixed, too.>
Thanks...
Chrissy and Chris
<Glad to help. Cheers, Neale.>

Sick Oscar, same as almost all... no reading or data of use 10/20/11
Yesterday I added another pump to my 40 gallon tank everything was fine at first. Then today I noticed my Oscar was swimming up in the new pumps bubbles He seemed to be enjoying himself. The other fish in the tank a black catfish and a algae eater would swim around him. About dinner time my daughter noticed Oscar had started swimming upside down. It was very sudden. I transferred him to a 2 gallon hospital tank
<? Two gallons?>
gave him a pea and some medicine for parasites.
<What for?>
But I don't see any bloated area on him, but his belly has a yellow color to it and his eyes are cloudy. Can my Oscar be saved?
<This volume is too small for these fishes... very likely water quality IS the issue here. Change a good deal of water out, vacuum the gravel... READ here: http://wetwebmedia.com/FWSubWebIndex/oscarsysfaqs.htm
and the linked files above. Bob Fenner>

Mysterious Oscar Killer 9/19/11
Hi wwm crew,
This is my first time writing to you guys and surprisingly (to me), it is about some fish we have a good deal of experience with, our Oscars. My parents bought a 75 gal tank 3 weeks ago and in their rush they fully stocked it with 4 Oscars, 5 guoramis (spelling?), 2 upside down cats, 2 silver dollars, and 2 tin foils. The smallest Oscar (our albino tiger) suddenly began hiding about 4 or 5 days into our ownership and died a week after bringing them home. We assumed (knowing how territorial these fish are as well as their general bossy attitude) that one of the three much larger Oscars stressed the poor guy to death. Then, a few days later our red Oscar ( the second largest) began hiding under our big wooden root structure (large piece of wood bought at PetSmart). When I went to check on the tank (one of many trips to my parents house) I was taking inventory of all the fish and got a good view of Red. He had Ick. I gently guided him to the side of the tank with the net to get a better look and take pics. He was very calm and came out with no trouble. He allowed me to take the pictures and went back to hiding. I immediately informed my parents and insisted on treatments and a quarantine tank(which I told them to get a week before lol). The next day we bought a ten gal glass, a filter, air bubble bar, tree to give shelter, herbal meds for fungi and bacteria, and rocks. The meds were suggested to us by the fish department lady. We set up the quarantine tank, siphoned off about 7 gals of water from the main tank and added two gals of treated tap, let it run and discovered a major leak in the ten gal and had to dump the water. We got a replacement tank the same night and got it set up and again siphoned 7 gal tank water to two gal tap. We refilled the main tank with treated tap. He seemed to be doing better in the ten gal though he would not eat. Both tank have been cycling through meds since the night of their purchase per instruction. Yesterday red died. We are down to two Oscars though every other type of fish has remained relatively unaffected. About the same day we put red in the ten gal, our largest Oscar, an albino, began sulking and hiding but still eating. He has no sign of Ick, fins in excellent condition but a small scrape on his side. He is no longer eating. The tin foils had a small amount of Ick that has almost fully cleared up. No other fish in the tank has shown signs of Ick. All but Oscars showing normal behavior and appetite. Please note that while I am working on water condition it still needs some work. Ph is good but nitrates are still high. I have a vacuuming and 30 gal water change planned for this evening. I want to add suckerfish but do not know if it is safe yet in my tank. Please help me! I have lost two Oscars n do not want to loose any more. I am sorry this email is so long but I am trying to give you all the info I can. Please help me to understand what this Oscar killer is. Is it bioload? Or an illness? Thanks so much for your advice and wonderful site. Be sure to look for my emails around Christmas related to a reef tank that is being given to my son as a Christmas gift.
Aesia
<Greetings. It does seem your aquarium is massively overstocked. One Oscar in a 75 gallon tank is a squeeze; four of them is insane! Even if they're only young, let's say anything above 12 cm/5 inches, this tank will be overstocked. Throw in big fish like the Tinfoil Barbs and you've got a recipe for disaster. Adding a Plec catfish would be lunacy, and simply isn't on the cards at all. Not only does this aquarium need to have most of its residents removed, the Plec/Oscar combination is an unreliable one, with the common Pterygoplichthys species especially being known "mucous grazers" that damage the flanks of Oscars when they try to scrape off the mucous. But let's not worry about that now, because you aren't adding any more fish to this tank! Let's focus on why your fish are dying. The thing with cichlids is that non-zero levels of ammonia and nitrite are especially dangerous, and even nitrate, which for most fish isn't too serious, starts sickening them at levels as low as 20 mg/l. On top of this, overstocked tanks have low levels of oxygen, and this is another cichlids won't tolerate for long. Basically you have an aquarium that isn't nearly big enough for the fish you're keeping; 200 gallons would be the sort of size for the fish you have, though whether four Oscars will tolerate one another once they start pairing off is a whole other discussion. Do read what these fish need, write up a shopping list, and make the necessary changes.
Otherwise return all but one Oscar, and if you want a companion for it, choose a robust species that won't graze its flanks, for example Synodontis euptera or Panaque nigrolineatus.
http://www.wetwebmedia.com/fwsubwebindex/oscars.htm
Cheers, Neale.>
Re: Mysterious Oscar Killer 9/22/11
Thank you so much Neale,
<Glad to help.>
Your insight helped to confirm ALL of my worst fears. After reading your email, I immediately looked up every fish my parents bought. I spoke with them about the information I gained and asked a few questions about the individual fish they bought and the live fish store they were bought from.
I was very disturbed to hear that the clerk at one fish store (no names but the tins, dollars, 2 Oscars, the cats and the gouramis were purchased here) recommended that my parents put more fish but also recommended they put in the tins, dollars and cats (while they are decent suggestions, not all together and not in a 75 gal tank.)
<I agree. All lovely fish, some of the best in fact, but your family have enough for a swimming pool!>
All about the Benjamins. We have been discussing solutions and here is what we have decided.
1. Return/trade in the tins,
<Could be wise. These fish are among the worst when it comes to housing because they're both active and big, so they need more space than an inactive fish of similar size. They're also social, which exacerbates things.>
2. Get a new tank for dollars, cats, and gouramis (I would like your suggestion on size here. I'm thinking maybe 50 or 60 here. And am also considering trading/returning the dollars.)
<Have seen 75, 100 gallon tanks with a combination of Gouramis and Australian Rainbowfish (Melanotaenia boesemanni for example) and these work extremely well together. Throw in some live or fake plants for greenery, and you have a winning aquarium that works well across a broad water chemistry range.>
3. Get 1 new Oscar (we lost our albino). Now my question here is can I add some hermits and snails since they r armored animals?
<Crabs are a major part of the diet of Oscars, as are snails to a lesser
degree. Look at those jaws -- they're massive! In the wild Oscars crunch on all sorts of shelled and armoured beasts, even small catfish like Corydoras!>
What about suckers?
<As I said, some Plecs can damage Oscars. Take a look at the photos close to the top of this page:
http://www.wetwebmedia.com/fwsubwebindex/OscarDisF11.htm
Both Bob Fenner and myself believe that this is a classic example of Plec damage. While this isn't common behaviour, it does happen. I'd choose the Suckermouth catfish extremely carefully. The best bets are the more-or-less herbivorous sorts like Panaque nigrolineatus rather than omnivores such as Pterygoplichthys species. Alternatively, there are some excellent Synodontis species like Synodontis euptera that will be just as good at eating any leftover food without being dangerous to your Oscar. Do remember, in an Oscar aquarium no catfish will prevent algae problems. Such a tank will have so much nitrate and phosphate, and likely few/no fast-growing plants, so that physical removal is really the only way forward. Floating plants might work well though.>
The Oscars will be all that's left in the 75 gal. Thank you again for your insight. Unfortunately, I was unable to prevent this incident but with your help I am in the position to fix it and prevent future instances of ignorance. Again, thank you guys for all you do. I look forward to your advice as I travel down the road of saltwater tanks in the near future, something I plan to take very slowly.
Aesia
<Saltwater is fun in many ways, and thanks to advances in filtration and live rock, much easier than many suppose. Bob Fenner's 'Conscientious Aquarist' book really is an excellent step-by-step cookbook guide, and you'll find it well worth borrowing or buying. Cheers, Neale.>